问题 解答题

把下列各式分解因式:

①3ax2-3ay2                

②m3+4m2+4m          

③(x2+y22-4x2y2

答案

①3ax2-3ay2

=3a(x2-y2

=3a(x+y)(x-y);

②m3+4m2+4m

=m(m2+4m+4)

=m(m+2)2

      

③(x2+y22-4x2y2

=(x2+y2+2xy)(x2+y2-2xy)

=(x+y)2(x-y)2

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