### Create a StudySoup account

#### Be part of our community, it's free to join!

Already have a StudySoup account? Login here

# Solving Exponential Equations Math 1610-090

Purdue

### View Full Document

## 22

## 2

## Popular in Calculus 1

## Popular in Department

This 6 page Class Notes was uploaded by sang on Monday June 13, 2016. The Class Notes belongs to Math 1610-090 at Purdue University taught by in Summer 2016. Since its upload, it has received 22 views.

## Similar to Math 1610-090 at Purdue

## Reviews for Solving Exponential Equations

### What is Karma?

#### Karma is the currency of StudySoup.

#### You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 06/13/16

Example 1 Solve each of the following. (a) [Solution] (b) [Solution] (c) [Solution] (d) [Solution] Solution (a) In this first part we have the same base on both exponentials so there really isn’t much to do other than to set the two exponents equal to each other and solve for x. So, if we were to plug into the equation then we would get the same number on both sides of the equal sign. [Return to Problems] (b) Again, there really isn’t much to do here other than set the exponents equal since the base is the same in both exponentials. In this case we get two solutions to the equation. That is perfectly acceptable so don’t worry about it when it happens. [Return to Problems] (c) Now, in this case we don’t have the same base so we can’t just set exponents equal. However, with a little manipulation of the right side we can get the same base on both exponents. To do this all we need to notice is that . Here’s what we get when we use this fact. Now, we still can’t just set exponents equal since the right side now has two exponents. If we recall our exponent properties we can fix this however. We now have the same base and a single exponent on each base so we can use the property and set the exponents equal. Doing this gives, So, after all that work we get a solution of . [Return to Problems] (d) In this part we’ve got some issues with both sides. First the right side is a fraction and the left side isn’t. That is not the problem that it might appear to be however, so for a second let’s ignore that. The real issue here is that we can’t write 8 as a power of 4 and we can’t write 4 as a power of 8 as we did in the previous part. The first thing to do in this problem is to get the same base on both sides and to so that we’ll have to note that we can write both 4 and 8 as a power of 2. So let’s do that. It’s now time to take care of the fraction on the right side. To do this we simply need to remember the following exponent property. Using this gives, So, we now have the same base and each base has a single exponent on it so we can set the exponents equal. And there is the answer to this part. [Return to Problems] Now, the equations in the previous set of examples all relied upon the fact that we were able to get the same base on both exponentials, but that just isn’t always possible. Consider the following equation. This is a fairly simple equation however the method we used in the previous examples just won’t work because we don’t know how to write 9 as a power of 7. In fact, if you think about it that is exactly what this equation is asking us to find. So, the method we used in the first set of examples won’t work. The problem here is that the x is in the exponent. Because of that all our knowledge about solving equations won’t do us any good. We need a way to get the x out of the exponent and luckily for us we have a way to do that. Recall the following logarithm property from the last section. Note that to avoid confusion with x’s we replaced the x in this property with an a. The important part of this property is that we can take an exponent and move it into the front of the term. So, if we had, we could use this property as follows. The x in now out of the exponent! Of course we are now stuck with a logarithm in the problem and not only that but we haven’t specified the base of the logarithm. The reality is that we can use any logarithm to do this so we should pick one that we can deal with. This usually means that we’ll work with the common logarithm or the natural logarithm. So, let’s work a set of examples to see how we actually use this idea to solve these equations.

### BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.

### You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

## Why people love StudySoup

#### "I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"

#### "When you're taking detailed notes and trying to help everyone else out in the class, it really helps you learn and understand the material...plus I made $280 on my first study guide!"

#### "There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

#### "It's a great way for students to improve their educational experience and it seemed like a product that everybody wants, so all the people participating are winning."

### Refund Policy

#### STUDYSOUP CANCELLATION POLICY

All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email support@studysoup.com

#### STUDYSOUP REFUND POLICY

StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here: support@studysoup.com

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to support@studysoup.com

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.