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Hi, here is my explanation to question 2:
2. If x <> 0, then square root (x^2) / x =
A. -1
B. 0
C. 1
D. x
E. abs(x)/x
Since x <> 0, it means x is a positive or a negative number. A negative number to the power of 2 is always positive, so in this question, we just need to worry about the x in the denominator. Remember, after the square root, you can't have a negative integer. For example sqrt(4) is 2 but sqrt(-4) is *not* good. Remember, 2^2 is 4 and (-2)^2 is also 4. Therefore, in this question, since the numerator is always postive, and the denominator *could* be negative, you need to absolute value it to make sure the answer is positive. Remember, in absolute value, |2| is 2 and |-2| is 2.
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