先化简再求值(3m²+5)(-3m²+5)-m²(7m+8)(7m+8)+(2m+1)(-2m-1),其中m=-1

问题描述:

先化简再求值(3m²+5)(-3m²+5)-m²(7m+8)(7m+8)+(2m+1)(-2m-1),其中m=-1

(3m²+5)(-3m²+5)-m²(7m+8)(7m-8)+(7m-8)+(m+1)(-2m-1)
=25-9m^4-49m^4+64m²+7m-8-2m²-3m-1
=-58m^4+62m²+4m+16
=-58+62-4+16
=16