In Fig. 35, indicate which point is the image of P under (a) the reflection with axis l1. (b) the reflection with axis l2. (c) the reflection with axis l3. (d) the reflection with axis l4.
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Table of Contents
Textbook Solutions for Excursions in Modern Mathematics: Pearson New International Edition
Question
In Fig. 46, A and B are fixed points of a reflection. Find the image of the shaded region under the reflection. figurE 46
Solution
The first step in solving 11 problem number 12 trying to solve the problem we have to refer to the textbook question: In Fig. 46, A and B are fixed points of a reflection. Find the image of the shaded region under the reflection. figurE 46
From the textbook chapter The Mathematics of Symmetry you will find a few key concepts needed to solve this.
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full solution
In Fig. 46, A and B are fixed points of a reflection. Find the image of the shaded
Chapter 11 textbook questions
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Chapter 11: Problem 1 Excursions in Modern Mathematics: Pearson New International Edition 8 -
Chapter 11: Problem 2 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 36, indicate which point is the image of P under (a) the reflection with axis l1. (b) the reflection with axis l2. (c) the reflection with axis l3. (d) the reflection with axis l4. figurE 36 C A B D E F G l2 l3 l4
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Chapter 11: Problem 3 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 37, A is the image of A under a reflection. (a) Find the axis of the reflection. (b) Find the image of A under the reflection.
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Chapter 11: Problem 4 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 38, P is the image of P under a reflection. (a) Find the axis of the reflection. (b) Find the image of P under the reflection. figurE 38
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Chapter 11: Problem 5 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 39, l is the axis of reflection. (a) Find the image of S under the reflection. (b) Find the image of quadrilateral PQRS under the reflection.
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Chapter 11: Problem 6 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 40, l is the axis of reflection. (a) Find the image of P under the reflection. (b) Find the image of the parallelogram PQRS under the reflection.
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Chapter 11: Problem 7 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 41, P is the image of P under a reflection. (a) Find the axis of the reflection. (b) Find the image of S under the reflection. (c) Find the image of the quadrilateral PQRS under the reflection. (d) Find a point on the quadrilateral PQRS that is a fixed point of the reflection.
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Chapter 11: Problem 8 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 42, P is the image of P under a reflection. (a) Find the axis of the reflection. (b) Find the image of S under the reflection. (c) Find the image of the quadrilateral PQRS under the reflection. (d) Find a point on the quadrilateral PQRS that is a fixed point of the reflection.
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Chapter 11: Problem 9 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 43, P is the image of P under a reflection. (a) Find the axis of the reflection. (b) Find the image of the shaded arrow under the reflection. figurE 43
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Chapter 11: Problem 10 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 44, is the image of R under a reflection. (a) Find the axis of reflection. (b) Find the image of the shaded arrow under the reflection.
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Chapter 11: Problem 11 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 45, A and B are fixed points of a reflection. Find the image of the shaded region under the reflection. figurE 45
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Chapter 11: Problem 12 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 46, A and B are fixed points of a reflection. Find the image of the shaded region under the reflection. figurE 46
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Chapter 11: Problem 13 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 47, indicate which point is (a) the image of B under a 90 clockwise rotation with rotocenter A. (b) the image of A under a 90 clockwise rotation with rotocenter B. (c) the image of D under a 60 clockwise rotation with rotocenter B. (d) the image of D under a 120 clockwise rotation with rotocenter B. (e) the image of I under a 3690 clockwise rotation with rotocenter A. figurE 47 H G C B A E D F
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Chapter 11: Problem 14 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 47, indicate which point is (a) the image of C under a 90 counterclockwise rotation with rotocenter B. (b) the image of F under a 60 clockwise rotation with rotocenter A. (c) the image of F under a 120 clockwise rotation with rotocenter B. (d) the image of I under a 90 clockwise rotation with rotocenter H. (e) the image of G under a 3870 counterclockwise rotation with rotocenter B.
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Chapter 11: Problem 15 Excursions in Modern Mathematics: Pearson New International Edition 8In each case, give an answer between 0 and 360. (a) A clockwise rotation by an angle of 710 is equivalent to a counterclockwise rotation by an angle of .
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Chapter 11: Problem 16 Excursions in Modern Mathematics: Pearson New International Edition 8In each case, give an answer between 0 and 360. (a) A clockwise rotation by an angle of 500 is equivalent to a clockwise rotation by an angle of . (b) A clockwise rotation by an angle of 500 is equivalent to a counterclockwise rotation by an angle of . (c) A clockwise rotation by an angle of 5000 is equivalent to a clockwise rotation by an angle of . (d) A clockwise rotation by an angle of 50,000 is equivalent to a counterclockwise rotation by an angle of .
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Chapter 11: Problem 17 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 48, a rotation moves B to B and C to C. (a) Find the rotocenter. (b) Find the image of triangle ABC under the rotation. figurE 48
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Chapter 11: Problem 18 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 49, a rotation moves A to A and B to B. (a) Find the rotocenter O. (b) Find the image of the shaded arrow under the rotation. figurE 49
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Chapter 11: Problem 19 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 50, a rotation moves A to A and B to B. (a) Find the rotocenter O. (b) Find the image of the shaded arrow under the rotation.
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Chapter 11: Problem 20 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 51, a rotation moves Q to Q and R to R. (a) Find the rotocenter. (b) Find the angle of rotation. (c) Find the image of quadrilateral PQRS under the rotation
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Chapter 11: Problem 21 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 52, find the image of triangle ABC under a 60 clockwise rotation with rotocenter O. figurE 52
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Chapter 11: Problem 22 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 53, find the image of ABCD under a 60 counterclockwise rotation with rotocenter O. figurE 53
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Chapter 11: Problem 23 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 54, indicate which point is the image of P under (a) the translation with vector v1. (b) the translation with vector v2. (c) the translation with vector v3. (d) the translation with vector v4. figurE 54
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Chapter 11: Problem 24 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 55, indicate which point is the image of P under (a) the translation with vector v1. (b) the translation with vector v2. (c) the translation with vector v3. (d) the translation with vector v4. figurE 55
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Chapter 11: Problem 25 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 56, E is the image of E under a translation. (a) Find the image of A under the translation. (b) Find the image of the shaded figure under the translation. (c) Draw a vector for the translation. figurE 56
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Chapter 11: Problem 26 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 57, Q’ is the image of Q under a translation. (a) Find the image of P under the translation. (b) Find the image of the shaded quadrilateral under the translation. (c) Draw a vector for the translation.
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Chapter 11: Problem 27 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 58, D is the image of D under a translation. Find the image of the shaded trapezoid under the translation. figurE 58
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Chapter 11: Problem 28 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 59, Qis the image of Q under a translation. Find the image of the shaded region under the translation. figurE 59
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Chapter 11: Problem 29 Excursions in Modern Mathematics: Pearson New International Edition 8Given a glide reflection with vector v and axis l as shown in Fig. 60, find the image of the triangle ABC under the glide reflection.
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Chapter 11: Problem 30 Excursions in Modern Mathematics: Pearson New International Edition 8Given a glide reflection with vector v and axis l as shown in Fig. 61, find the image of the quadrilateral ABCD under the glide reflection. figurE 61
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Chapter 11: Problem 31 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 62, D is the image of D under a glide reflection having axis l. Find the image of the polygon ABCDE under the glide reflection. figurE 62
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Chapter 11: Problem 32 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 63, P is the image of P under a glide reflection having axis l. Find the image of the quadrilateral PQRS under the glide reflection. figurE 63
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Chapter 11: Problem 33 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 64, B is the image of B and D is the image of D under a glide reflection. (a) Find the axis of reflection. (b) Find the image of A under the glide reflection. (c) Find the image of the shaded figure under the glide reflection. figurE 64
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Chapter 11: Problem 34 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 65, A is the image of A and C is the image of C under a glide reflection. (a) Find the axis of reflection. (b) Find the image of B under the glide reflection. (c) Find the image of the shaded figure under the glide reflection. figurE 65 B C D
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Chapter 11: Problem 35 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 66, P is the image of P and Q is the image of Q under a glide reflection. Find the image of the shaded figure under the glide reflection. figurE 66
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Chapter 11: Problem 36 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 67, P is the image of P and Q is the image of Q under a glide reflection. Find the image of the shaded figure under the glide reflection.
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Chapter 11: Problem 37 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 68, D is the image of D and C is the image of C under a glide reflection. Find the image of the shaded figure under the glide reflection.
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Chapter 11: Problem 38 Excursions in Modern Mathematics: Pearson New International Edition 8In Fig. 69, A is the image of A and D is the image of D under a glide reflection. Find the image of the shaded figure under the glide reflection.
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Chapter 11: Problem 39 Excursions in Modern Mathematics: Pearson New International Edition 8List the symmetries of each object shown in Fig. 70. (Describe each symmetry by giving specificsthe axes of reflection, the centers and angles of rotation, etc.) figurE 70 A B D C (a) A B D C (b) A B D C (c)
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Chapter 11: Problem 40 Excursions in Modern Mathematics: Pearson New International Edition 8List the symmetries of each object shown in Fig. 71. (Describe each symmetry by giving specificsthe axes of reflection, the centers and angles of rotation, etc.) A C B 45 45 (a) A C B 60 60 60 (b) A BC 60 30 (c) figurE 71
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Chapter 11: Problem 41 Excursions in Modern Mathematics: Pearson New International Edition 8List the symmetries of each object shown in Fig. 72. (Describe each symmetry by giving specificsthe axes of reflection, the centers and angles of rotation, etc.)
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Chapter 11: Problem 42 Excursions in Modern Mathematics: Pearson New International Edition 8List the symmetries of each object shown in Fig. 73. (Describe each symmetry by giving specificsthe axes of reflection, the centers and angles of rotation, etc.) (a) (b)
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Chapter 11: Problem 43 Excursions in Modern Mathematics: Pearson New International Edition 8For each of the objects in Exercise 39, give its symmetry type.
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Chapter 11: Problem 44 Excursions in Modern Mathematics: Pearson New International Edition 8For each of the objects in Exercise 40, give its symmetry type.
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Chapter 11: Problem 45 Excursions in Modern Mathematics: Pearson New International Edition 8For each of the objects in Exercise 41, give its symmetry type
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Chapter 11: Problem 46 Excursions in Modern Mathematics: Pearson New International Edition 8For each of the objects in Exercise 42, give its symmetry type.
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Chapter 11: Problem 47 Excursions in Modern Mathematics: Pearson New International Edition 8Find the symmetry type for each of the following letters. (a) A (b) D (c) L (d) Z (e) H (f) N
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Chapter 11: Problem 48 Excursions in Modern Mathematics: Pearson New International Edition 8Find the symmetry type for each of the following symbols. (a) $ (b) @ (c) % (d) : (e) &
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Chapter 11: Problem 49 Excursions in Modern Mathematics: Pearson New International Edition 8Give an example of a capital letter of the alphabet that has symmetry type (a) Z1. (b) D1. (c) Z2. (d) D2.
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Chapter 11: Problem 50 Excursions in Modern Mathematics: Pearson New International Edition 8Give an example of a one- or two-digit number that has symmetry type (a) Z1. (b) D1. (c) Z2. (d) D2.
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Chapter 11: Problem 51 Excursions in Modern Mathematics: Pearson New International Edition 8Classify each border pattern by its symmetry type. Use the standard crystallographic notation (mm, mg, m1, 1m, 1g, 12, or 11). (a) . . . A A A A A . . . . . . D D D D D . . . . . . Z Z Z Z Z . . . . . . L L L L L
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Chapter 11: Problem 52 Excursions in Modern Mathematics: Pearson New International Edition 8Classify each border pattern by its symmetry type. Use the standard crystallographic notation (mm, mg, m1, 1m, 1g, 12, or 11). (a) N N N N N WWWWW H H H H H J J J J J (b) (c) (d
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Chapter 11: Problem 53 Excursions in Modern Mathematics: Pearson New International Edition 8Classify each border pattern by its symmetry type. Use the standard crystallographic notation (mm, mg, m1, 1m, 1g, 12, or 11). (a) qpqpqpqp pdpdpdpd pbpbpbpb pqbdpqbd (b) (c) (d
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Chapter 11: Problem 54 Excursions in Modern Mathematics: Pearson New International Edition 8Classify each border pattern by its symmetry type. Use the standard crystallographic notation (mm, mg, m1, 1m, 1g, 12, or 11). (a) qbqbqbqb qdqdqdqd dbdbdbdb qpdbqpdb (b) (c) (d)
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Chapter 11: Problem 55 Excursions in Modern Mathematics: Pearson New International Edition 8If a border pattern consists of repeating a motif of symmetry type Z2, what is the symmetry type of the border pattern?
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Chapter 11: Problem 56 Excursions in Modern Mathematics: Pearson New International Edition 8If a border pattern consists of repeating a motif of symmetry type Z1, what is the symmetry type of the border pattern?
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Chapter 11: Problem 57 Excursions in Modern Mathematics: Pearson New International Edition 8Imagine a border pattern of type m1 placed between parallel lines l1 and l2 (Fig. 74). Create a new border pattern twice the height by reflecting a copy of the original pattern about l2. What is the symmetry type of the new border pattern?
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Chapter 11: Problem 58 Excursions in Modern Mathematics: Pearson New International Edition 8Imagine a border pattern of type 12 placed between parallel lines l1 and l2 (Fig. 74). Create a new border pattern twice the height by rotating a copy of the original pattern 180 degrees and gluing both copies along line l2. What is the symmetry type of this new border pattern?
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Chapter 11: Problem 59 Excursions in Modern Mathematics: Pearson New International Edition 8The minute hand of a clock is pointing at the number 9, and it is then wound clockwise 7080 degrees. (a) How many full hours has the hour hand moved? (b) At what number on the clock does the minute hand point at the end?
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Chapter 11: Problem 60 Excursions in Modern Mathematics: Pearson New International Edition 8Name the rigid motion (translation, reflection, glide reflection, or rotation) that moves footprint 1 onto footprint (a) 2 (b) 3 (c) 4 (d) 5 1 2 4 3 5 figurE 75
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Chapter 11: Problem 61 Excursions in Modern Mathematics: Pearson New International Edition 8In each case, determine whether the rigid motion is a reflection, rotation, translation, or glide reflection or the identity motion. (a) The rigid motion is proper and has exactly one fixed point. (b) The rigid motion is proper and has infinitely many fixed points. (c) The rigid motion is improper and has infinitely many fixed points. (d) The rigid motion is improper and has no fixed points.
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Chapter 11: Problem 62 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .In Fig. 76, l1, l2, l3, and l4 are axes of reflection. In each case, indicate which point is the image of P under (a) the product of the reflection with axis l1 and the reflection with axis l2. (b) the product of the reflection with axis l2 and the reflection with axis l1. (c) the product of the reflection with axis l2 and the reflection with axis l3. (d) the product of the reflection with axis l3 and the reflection with axis l2. (e) the product of the reflection with axis l1 and the reflection with axis l4
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Chapter 11: Problem 63 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .In Fig. 77, indicate which point is the image of P under (a) the product of the reflection with axis l and the 90 clockwise rotation with rotocenter A. (b) the product of the 90 clockwise rotation with rotocenter A and the reflection with axis l. (c) the product of the reflection with axis l and the 180 rotation with rotocenter A. (d) the product of the 180 rotation with rotocenter A and the reflection with axis l.
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Chapter 11: Problem 64 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .In each case, state whether the rigid motion is proper or improper. (a) is the product of a proper rigid motion and an improper rigid motion. (b) is the product of an improper rigid motion and an improper rigid motion. (c) is the product of a reflection and a rotation. (d) is the product of two reflections.
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Chapter 11: Problem 65 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .Suppose that a rigid motion is the product of a reflection with axis l1 and a reflection with axis l2, where l1 and l2 intersect at a point C. Explain why must be a rotation with center C.
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Chapter 11: Problem 66 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .Suppose that the rigid motion is the product of the reflection with axis l1 and the reflection with axis l3, where l1 and l3 are parallel. Explain why must be a translation.
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Chapter 11: Problem 67 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .In Fig. 78, l1 and l2 intersect at C, and the angle between them is a. (a) Give the rotocenter, angle, and direction of rotation of the product of the reflection with axis l1 and the reflection with axis l2.
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Chapter 11: Problem 68 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .In Fig. 79, l1 and l3 are parallel and the distance between them is d. (a) Give the length and direction of the vector of the translation that is the product of the reflection with axis l1 and the reflection with axis l3. (b) Give the length and direction of the vector of the translation that is the product of the reflection with axis l3 and the reflection with axis l1. figurE 79
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Chapter 11: Problem 69 Excursions in Modern Mathematics: Pearson New International Edition 8Exercises 62 through 69 deal with combining rigid motions. Given two rigid motions and , we can combine the two rigid motions by first applying and then applying to the result. The rigid motion defined by combining and ( goes first, goes second) is called the product of and .In Fig. 80, P is the image of P under a translation and Q is the image of Q under a translation . (a) Find the images of P and Q under the product of and . (b) Show that the product of and is a translation. Give a geometric description of the vector of the translation.
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Chapter 11: Problem 70 Excursions in Modern Mathematics: Pearson New International Edition 8(a) Explain why a border pattern cannot have a reflection symmetry along an axis forming a 45 angle with the direction of the pattern. (b) Explain why a border pattern can have only horizontal and/or vertical reflection symmetry
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Chapter 11: Problem 71 Excursions in Modern Mathematics: Pearson New International Edition 8A rigid motion moves the triangle PQR into the triangle PQR as shown in Fig. 81. Explain why the rigid motion must be a glide reflection.
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Chapter 11: Problem 72 Excursions in Modern Mathematics: Pearson New International Edition 8Construct border patterns for each of the seven symmetry types using copies of the symbol 1 (and rotated versions of it).
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Chapter 11: Problem 73 Excursions in Modern Mathematics: Pearson New International Edition 8Let the six symmetries of the equilateral triangle ABC shown in Fig. 82 be denoted as follows: r1 denotes the reflection with axis l1; r2 denotes the reflection with axis l2; r3 denotes the reflection with axis l3; R1 denotes the 120 clockwise rotation with rotocenter O; R2 denotes the 240 clockwise rotation with rotocenter O; I denotes the identity symmetry. Complete the symmetry multiplication table by entering, in each row and column of the table, the product of the row and the column (i.e., the result of applying first the symmetry in the row and then the symmetry in the column). For example, the entry in row r1 and column r2 is R1 because the product of the reflection r1 and the reflection r2 is the rotation R1
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Chapter 11: Problem 74 Excursions in Modern Mathematics: Pearson New International Edition 8Let the eight symmetries of the square ABCD shown in Fig. 83 be denoted as follows: r1 denotes the reflection with axis l1; r2 denotes the reflection with axis l2; r3 denotes the reflection with axis l3; r4 denotes the reflection with axis l4; R1 denotes the 90 clockwise rotation with rotocenter O; R2 denotes the 180 clockwise rotation with rotocenter O; R3 denotes the 270 clockwise rotation with rotocenter O; I denotes the identity symmetry. Complete the symmetry multiplication table below (Hint: Try Exercise 73 first.) A l1 l2 l3 l4 B D C O
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Chapter 11: Problem 75 Excursions in Modern Mathematics: Pearson New International Edition 8List all the symmetries of the wallpaper pattern shown in Fig. 84.
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Chapter 11: Problem 76 Excursions in Modern Mathematics: Pearson New International Edition 8List all the symmetries of the wallpaper pattern shown in Fig. 85.
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Chapter 11: Problem 77 Excursions in Modern Mathematics: Pearson New International Edition 8List all the symmetries of the wallpaper pattern shown in Fig. 86
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Chapter 11: Problem 78 Excursions in Modern Mathematics: Pearson New International Edition 8List all the symmetries of the wallpaper pattern shown in Fig. 87.
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Chapter 11: Problem 79 Excursions in Modern Mathematics: Pearson New International Edition 8List all the symmetries of the wallpaper pattern shown in Fig. 88. figurE 88
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Chapter 11: Problem 80 Excursions in Modern Mathematics: Pearson New International Edition 8List all the symmetries of the wallpaper pattern shown in Fig. 89. figurE 89
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