For the Arithmetic Section Excerise 8, it asks for square root of (-3)2. Greg decided to take the approach of PEMDAS, which makes sense, but one of the rules of roots is that sqrt(a2) = a. This is Rule 2 of the Roots from the ETS Math Review packet. What makes the difference? Why is there an unclear discrepancy between the two?
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Please format your posts (using \LaTeX or otherwise).
Now, to find \sqrt{-3^2}, you first operate inside the square root. This gives you \sqrt{9}, because -3 \times -3 = 9. Then \sqrt{9} = 3.
Will use Latex next time.
I understand the use of PEMDAS like the operation you used to solve the problem, but what is the difference between using this and using Rule 2 of the Roots? They both give two different answers.
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Link me the session from which you got the problem.
Never mind, found it, but in future do link.
In the previous page of the Math Review (the end of page 13), it says that (emphasis mine):
Here are four important rules regarding operations with square roots, where a > 0 and
b > 0.
-3 is not greater than 0, and hence the rule does not work there.
I see thank you!