If log2(x),log2(x2),log2(x4)log_2(x), log_2(x^2), log_2(x^4)log2(x),log2(x2),log2(x4) form a geometric sequence, what must be true about xxx?
x>0x > 0x>0
x≠1x \neq 1x=1
x=2x = 2x=2
x=1/2x = 1/2x=1/2