[求助]GWD29-3

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Q3:

If n is an integer and xⁿ – x^-n = 0, what is the value of x ?

(1)       x is an integer.

(2)       n ≠ 0

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient.

Answer:

the answer is E, but i think its D.

i got it..

3 q very much!!