3a²+2ab=5,3b²+2ab=2,a²-b²=
问题描述:
3a²+2ab=5,3b²+2ab=2,a²-b²=
答
1
答
3a²+2ab=5,3b²+2ab=2,
两个式子相减
3a²-3b²=3
所以a²-b²=1