Question

急用!三道因式分解x的（m+3）次方+x的（2m+2）次方-3x的（2m+1）次方多项式x平方-2xy+ky平方+3x-

Answer 1

5x³-2x²y+8y-20x

=x²(5x-2y)-4(5x-2y)

=(5x-2y)(x²-2²)

=(5x-2y)(x+2)（x-2）

4-16y²-20ay²+5a

=4(1-4y²)+5a(1-4y²)

=(1-4y²)(4+5a)

=(1+2y)(1-2y)(4+5a)

a³+3a²b+ab²+3b³

=a²(a+3b)+b²(a+3b)

=(a+3b)(a²+b²)

打字不易,