x²-(x-5)(x+1)=?
问题描述:
x²-(x-5)(x+1)=?
答
原式=x²-(x²-4x-5)
=x²-x²+4x+5
=4x+5
x²-(x-5)(x+1)=?
原式=x²-(x²-4x-5)
=x²-x²+4x+5
=4x+5