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## #1 2023-09-08 11:53:46

harpazo1965
Member
Registered: 2022-09-19
Posts: 129

### Principal Square Root

College Algebra
Section R.2

Michael Sullivan introduces the idea of square roots on page 24.

According to Sullivan:

sqrt{ a^2 } = | a |, where "a" is any real number.

Sample:

sqrt{ x^2 } = | x |.

Why is the answer the absolute value of x and not simple x?

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## #2 2023-09-08 21:49:00

Bob
Registered: 2010-06-20
Posts: 9,719

### Re: Principal Square Root

Because x could be negative and he is trying to define a unique positive root.

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #3 2023-09-09 03:07:14

harpazo1965
Member
Registered: 2022-09-19
Posts: 129

### Re: Principal Square Root

Are you saying that the sqrt{ x^(2) } = -x or x?
To assure a positive x, we place the variable x inside absolute value bars.

Yes?

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## #4 2023-09-09 21:45:51

Bob
Registered: 2010-06-20
Posts: 9,719

### Re: Principal Square Root

Yes.

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #5 2023-09-10 10:08:35

harpazo1965
Member
Registered: 2022-09-19
Posts: 129

Thank you, Bob.

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