先化简再求值[(3a-7)^2-(a+5)^2]\(4a-24)其中a=0.02

分类: 作业答案 • 2021-12-28 14:14:15

问题描述：

答

[(3a-7)^2-(a+5)^2]\(4a-24)
=[(3a-7+a+5)*(3a-7-a-5)]/(4a-24)
=(4a-2)*(2a-12)/(4a-24)
=(2a-1)(a-6)/(a-6)
=2a-1
=2×0.02-1
=0.04-1
=-0.96