SOLUTION: Given an example to show that the sqrt{a^2} is not equal to a. Use it to explain why sqrt{a^2} = | a |.

Algebra.Com
Question 1208654: Given an example to show that the sqrt{a^2} is not equal to a.
Use it to explain why sqrt{a^2} = | a |.

Answer by Shin123(626)   (Show Source): You can put this solution on YOUR website!
For an example, let's say . Then, , which is not equal to -1.

Note that the square root function always takes the principal square root (the nonnegative one). If is positive, then will still be , since that is the principal square root. If is negative, then will be , since the two square roots are and , and is the principal square root. ( is negative, so is positive). If is 0, then is also just . Note that this is the exact definition of |a|. The absolute value function leaves positive numbers and zero unchanged, while taking the negative of negative numbers to make them positive. (same thing the square root function did).

RELATED QUESTIONS

Give an example to show that sqrt{a^2} is not equal to a. Use it to explain why sqrt{a^2} (answered by mccravyedwin)
Give an example to show that sqrt{a^(2)} is not equal to a. Use it to explain why... (answered by math_tutor2020)
How do i go about factoring: sqrt(128) I looked online on how to solve radicals and i... (answered by oscargut)
Give an example of numbers a and b that show {{{sqrt(A + B)}}} is not the same as... (answered by Edwin McCravy)
Given: cos (-105) Find the exact value of the function without the use of a calculator. (answered by ikleyn)
What sort of approach should i do, when im faced with a question such as: Given that... (answered by robertb)
Can someone help me with this i've tried and i am not ending up with the right solutions. (answered by tutorcecilia)
I an using the Pythagorean theorem to find the horizontal side of a right triangle. The... (answered by stanbon)
Ron is puzzled. When he uses a graphing calculator to graph y = [sqrt] x * [sqrt] x... (answered by user_dude2008)