> 数学 >
已知m2+2n2-6m+8n+17=0,求(2m-n)2-(3n-m)的值
人气:196 ℃ 时间:2020-03-21 07:06:14
解答
m²+2n²-6m+8n+17=0
(m²-6m+9)+2(n²+4n+4)=0
(m-3)²+2(n+2)²=0
m-3=0,n+2=0
m=3,n=-2
(2m-n)²-(3n-m)
=(6+2)²-(-6-3)
=64+9
=73
推荐
猜你喜欢
© 2024 79432.Com All Rights Reserved.
电脑版|手机版