作业帮已知(a+2)²+b+5的绝对值=0求3a²b-[2a²b-(2ab-a²b)-4a²]-ab
来源：学生作业帮助网 编辑：作业帮 时间：2024/04/20 23:18:24
![已知(a+2)²+b+5的绝对值=0求3a²b-[2a²b-(2ab-a²b)-4a²]-ab](/uploads/image/z/135292-4-2.jpg?t=%E5%B7%B2%E7%9F%A5%28a%2B2%29%26%23178%3B%2Bb%2B5%E7%9A%84%E7%BB%9D%E5%AF%B9%E5%80%BC%3D0%E6%B1%823a%26%23178%3Bb-%5B2a%26%23178%3Bb-%282ab-a%26%23178%3Bb%29-4a%26%23178%3B%5D-ab)
已知(a+2)²+b+5的绝对值=0求3a²b-[2a²b-(2ab-a²b)-4a²]-ab
已知(a+2)²+b+5的绝对值=0求3a²b-[2a²b-(2ab-a²b)-4a²]-ab
已知(a+2)²+b+5的绝对值=0求3a²b-[2a²b-(2ab-a²b)-4a²]-ab
∵(a+2)²+lb+5l=0
∴a+2=0 且 b+5=0
∴a=-2,b=-5,
3a²b-[2a²b-(2ab-a²b)-4a²]-ab
=3a²b-2a²b+(2ab-a²b)+4a²-ab
=3a²b-2a²b+2ab-a²b+4a²-ab
=ab+4a²
=(-2)*(-5)+4*(-2)²
=10+16
=26