Rule:√(x^2) is equal to |x|
GMAT Prep - Roots
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iamcste
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If x=9
LHS=√(x^2)=√(9^2)=+9 or -9
RHS=|x|=|9|=+9 or -9 ( as we dont know whether X is positive or negative)
LHS=RHS
√(x^2) is equal to |x|
Isn't the absolute value of x divided by x equal to 1?
No, we dont know that X is positive or negative
hence, it could be +1 or -1
LHS=√(x^2)=√(9^2)=+9 or -9
RHS=|x|=|9|=+9 or -9 ( as we dont know whether X is positive or negative)
LHS=RHS
√(x^2) is equal to |x|
Isn't the absolute value of x divided by x equal to 1?
No, we dont know that X is positive or negative
hence, it could be +1 or -1

















