因式分解x^2-9y^2-4x+4 x^4-25x^2+60x-36
问题描述：
因式分解x^2-9y^2-4x+4 x^4-25x^2+60x-36
答
x" - 9y" - 4x + 4= x" - 4x + 4 - 9y"= x" - 2x - 2x + 4 - 9y"= x( x - 2 ) - 2( x - 2 ) - 9y"= ( x - 2 )" - ( 3y )"= ( x + 3y - 2 )( x - 3y - 2 )x^4 - 25x" + 60x - 36= x^4 - [ 25x" - 60x + 36 ]= x^4 - [...