Pearson Algebra 2 Common Core, 2011
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Pearson Algebra 2 Common Core, 2011 View details
6. Analyzing Data
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Exercise 43 Page 718

If a^n=b, where a and b are real numbers and n is a positive integer, then a is an n^\text{th} root of b. How many real n^\text{th} roots are there for positive b if n is even?

± 19/5

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If a^n= b, where a and b are real numbers and n is a positive integer, then a is an {\color{#009600}{n}}^\text{th} root of b. In our case, we want to find all the real 2^\text{nd} roots of 36125. a^2= 361/25 Because n=2 is even and b= 36125 is positive, there are two 2^\text{nd} roots of 36125. Positive Root:& a_1= sqrt(361/25) Negative Root:& a_2=-sqrt(361/25) Let's start with the positive root. Since the 2^\text{nd} roots are squares, we will first write b= 36125 as a power with an exponent of 2.

a_1=sqrt(361/25)
a_1=sqrt(19^2/5^2)
a_1=19/5

We found the positive 2^\text{nd} root of 195, which also gives us the negative root. Positive Root: &a_1= 19/5 Negative Root: &a_2=- 19/5