因式分解:① (x+y)^2-(3x-2y)^2 ②9(2a+3b)^2-25(3a-b)^2 ③a^3+4a^2b+4ab^2 (每道题要过程,谢谢)
问题描述:
因式分解:① (x+y)^2-(3x-2y)^2 ②9(2a+3b)^2-25(3a-b)^2 ③a^3+4a^2b+4ab^2 (每道题要过程,谢谢)
答
①(x+y)²-(3x-2y)²=[(x+y)+(3x-2y)][(x+y)-(3x-2y)]=(4x-y)(-2x+3y)②9(2a+3b)²-25(3a-b)²=[3(2a+3b)+5(3a-b)][3(2a+3b)-5(3a-b)]=(21a+4b)(-9a+14b)③a³+4a²b+4ab²=a(a²+4...