http://wenku.baidu.com/search?word=%C6%DF%C4%EA%BC%B6%CF%C2%CA%FD%D1%A7%CA%AE%D2%BB%D5%C2%CD%BC%D0%CE%B5%C4%C8%AB%B5%C8%CA%D4%BE%ED%B4%F0%B0%B8&lm=0&od=0
看看是不是,还是
http://wenku.baidu.com/search?word=%C6%DF%C4%EA%BC%B6%CF%C2%CA%FD%D1%A7%B5%A5%D4%AA%BC%EC%B2%E2%CA%AE%D2%BB%B4%F0%B0%B8&lm=0&od=0
4x^2yz+12x^3y =4X^2Y(Z+3X)
-3x^2-12x-12 =-3(X^2+4X+4)=-3(X+2)^2
(x-y)^2-(y-z)^2 =(X-Y+Y-Z)(X-Y-Y+Z)=(X-Z)(X-2Y+Z)
x^2+5x-6=(X-1)(X+6)
ax+bxy+bx+axy =aX(1+Y)+bX(1+Y)=X(1+Y)(a+b)
选择题