What is the value of x?
1) (-x)^3 = -x^3
2) (-x)^2 = -x^2
What is the value of x?
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1) (-x)^3 = -x^3
-x X -x X -x = -x^3
which means -x^3 = -x^3, means x^3 = x^3 x can be 0, 1, 2, -1 for that matter any value of X will satisfy. No sufficiency
2) (-x)^2 = -x^2
-x X -x = -x^2
x^2 = -x^2 means 2 x^2=0 means x^2=0 means x=0
B is sufficient
Is OA B? or Did I miss some thing?
-x X -x X -x = -x^3
which means -x^3 = -x^3, means x^3 = x^3 x can be 0, 1, 2, -1 for that matter any value of X will satisfy. No sufficiency
2) (-x)^2 = -x^2
-x X -x = -x^2
x^2 = -x^2 means 2 x^2=0 means x^2=0 means x=0
B is sufficient
Is OA B? or Did I miss some thing?
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The answer to this question would be B.
Statement (1) is essentially an identity. It holds true for any value of x. I'll prove it.
(-x)^3 = -x^3 can be expressed as
((-1)^3) * (x^3) = -x^3. Simplifying, we have
-x^3 = -x^3, which is true for any value of x.
Statement (2), on the other hand, can only be satisfied when x is 0.
(-x) ^ 2 = -x^2 can be expressed as
((-1)^2) * (x^2) = -x^2. Simplifying, we have
x^2 = -x^2.
This is only true if x = 0, so statement (2) alone is sufficient to solve for x. So, the answer is B.
Statement (1) is essentially an identity. It holds true for any value of x. I'll prove it.
(-x)^3 = -x^3 can be expressed as
((-1)^3) * (x^3) = -x^3. Simplifying, we have
-x^3 = -x^3, which is true for any value of x.
Statement (2), on the other hand, can only be satisfied when x is 0.
(-x) ^ 2 = -x^2 can be expressed as
((-1)^2) * (x^2) = -x^2. Simplifying, we have
x^2 = -x^2.
This is only true if x = 0, so statement (2) alone is sufficient to solve for x. So, the answer is B.
Tatiana Becker | GMAT Instructor | Veritas Prep