12x²-11xy-15y²=(4x+3y)(3x-5y)
-20xy+64x²+x²(题目?)→64x²-20xy+y²=(16x-y)(4x-y)
4x²+24xy+27y²=(2x+3y)(2x+9y)
xy-1-x+y=x(y-1)-(y-1)=(y-1)(x-1)
m²-n²+2n-1=m²-(n²-2n+1)=m²-(n-1)²=(m+n-1)(m-n+1)
x²+y²-9z²-1-2xy-6z=x²-2xy+y²-(9z²+6z+1)=(x-y)²-(3z+1)²=(x-y+3z+1)(x-y-3z-1)
能在帮我算两道吗
5x²-2x-1
3x²-4x-1
5x²-2x-1确认x²的系数是5?
3x²-4x-1确认常数项的系数是-1而不+1?
5x²-2x-1=5x²-2x-1-2+2=5x²-2x-3+2=(5x+3)(x-1)+2
3x²-4x-1=3x²-4x-1+1-1=3x²-4x+1-2=(3x-1)(x-1)-2
因式分解结果不是得要什么乘什么的吗,要求是在实数范围内