来自谭献海的问题
【已知a+b=3,ab=-2,求(3a+5ab)-(3ab-3b)的值(注:】
已知a+b=3,ab=-2,求(3a+5ab)-(3ab-3b)的值
(注:
1回答
2020-09-09 13:29
【已知a+b=3,ab=-2,求(3a+5ab)-(3ab-3b)的值(注:】
已知a+b=3,ab=-2,求(3a+5ab)-(3ab-3b)的值
(注:
(3a+5ab)-(3ab-3b)
=3a+5ab-3ab+3b
=3a+3b+2ab
=3×(a+b)+2ab
=3×3+2×(-2)
=9-4
=5