先化简后求职,(1)4(m+1)²-(2m+5)(2m-5),其中m=-3
问题描述:
先化简后求职,(1)4(m+1)²-(2m+5)(2m-5),其中m=-3
先化简后求职
答
4(m+1)²-(2m+5)(2m-5)
=4m²+8m+4-4m²+25
=8m+29
当m=-3时
原式=8*(-3)+29
=-24+29
=5