先化简,再求值:(1-4y)(1+4y)+(1+4y)²,其中y=2/8.

问题描述:

先化简,再求值:(1-4y)(1+4y)+(1+4y)²,其中y=2/8.

(1-4y)(1+4y)+(1+4y)²
=(1+4y)(1-4y+1+4y)
=2(1+4y)
=2+8y
=2+8×2/8
=2+2
=4