已知(a+2)²+丨b+3丨=0求1/3(9ab²-3)+(7a²b-2)+2(ab²+1)-2a²b
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/21 09:47:50
![已知(a+2)²+丨b+3丨=0求1/3(9ab²-3)+(7a²b-2)+2(ab²+1)-2a²b](/uploads/image/z/10143911-47-1.jpg?t=%E5%B7%B2%E7%9F%A5%EF%BC%88a%2B2%EF%BC%89%26%23178%3B%2B%E4%B8%A8b%2B3%E4%B8%A8%3D0%E6%B1%821%2F3%EF%BC%889ab%26%23178%3B-3%EF%BC%89%2B%EF%BC%887a%26%23178%3Bb-2%EF%BC%89%2B2%EF%BC%88ab%26%23178%3B%2B1%EF%BC%89-2a%26%23178%3Bb)
已知(a+2)²+丨b+3丨=0求1/3(9ab²-3)+(7a²b-2)+2(ab²+1)-2a²b
已知(a+2)²+丨b+3丨=0求1/3(9ab²-3)+(7a²b-2)+2(ab²+1)-2a²b
已知(a+2)²+丨b+3丨=0求1/3(9ab²-3)+(7a²b-2)+2(ab²+1)-2a²b
(a+2)²+丨b+3丨=0
所以
(a+2)²=0,丨b+3丨=0
a=-2
b=-3
所以
1/3(9ab²-3)+(7a²b-2)+2(ab²+1)-2a²b
=3ab²-1+7a²b-2+2ab²+2-2a²b
=5ab²+5a²b-1
=5ab(a+b)-1
=5×2×3×(-5)-1
=-150-1
=-151
原式=3ab^2-1+7a^2b-2+2ab^2+2-2a^2b
=5ab^2+5a^2b-1
=5ab(b+a)-1
(a+2)^2+(b+3)^2=0
a=-2
b=-3
原式=-151