问题
解答题
把下列各式分解因式:
①a2+10a+25
②m2-12mn+36n2
③xy3-2x2y2+x3y
④(x2+4y2)2-16x2y2
答案
①a2+10a+25,
=(a+5)2;
②m2-12mn+36n2
=(m-6n)2;
③xy3-2x2y2+x3y,
=xy(y2-2xy+x2),
=xy(x-y)2;
④(x2+4y2)2-16x2y2,
=(x2+4y2+4xy)(x2+4y2-4xy),
=(x+2y)2(x-2y)2.