*****求好心人教初中恒等式!****
问题描述：
*****求好心人教初中恒等式!****
ax^3+bx^2-18x=+8恒等(ax+2)(x^2+3x+4) 求A,B值
(x+1)(x+2)+A(x+3)+B恒等X^2 求A,B值
A(x-2)^2+B(X-2)(X+3)+C(X+3)恒等50求A,B值
答
①右边=ax^3+3ax^2+4ax+2x^2+6x+8 =ax^3+(3a+2)x^2+(4a+6)x+8∵左边恒等于右边∴{a=a,3a+2=b,4a+6=-18解得：a=-6,b=-16②左边=x^2+3x+2+Ax+3A+B=x^2+(3+A)x+(2+3A+B)=右边∴{3+A=0,2+3A+B=0...