已知x的2n次方=2,求(x的3m次方)²-8(-x)²的2n的值

问题描述:

已知x的2n次方=2,求(x的3m次方)²-8(-x)²的2n的值

(x的3n次方)²-8(-x)²的2n
=((x的2m次方)³-8(x的2n)²
=2³-8*2²
=8-32
=-24

x的2n次方=2,
(x的3n次方)²-8(-x)²的2n
=x的6n次方-8x的4n次方
=(x的n次方)的6次方-8(x的n次方)的4次方
=2的6次方-8×2的4次方
=64-128
=-64