x³+ax²-(a+2)x+3a-6能被x²+2x+3整除且商式为Ax+B
x³+ax²-(a+2)x+3a-6=(x²+2x+3)(Ax+B)
x³+ax²-(a+2)x+3a-6=Ax^3+2Ax^2+3Ax+Bx^2+2Bx+3B
x³+ax²-(a+2)x+3a-6=Ax^3+(2A+B)x^2+(3A+2B)x+3B
A=1 2A+B=a 3A+2B=-(a+2) 3B=3a-6
A=1 B=-7/3 a=-1/3
x³+ax²-(a+2)x+3a-6能被x²+2x+3整除且商式为Ax+B
x³+ax²-(a+2)x+3a-6=(x²+2x+3)(Ax+B)
x³+ax²-(a+2)x+3a-6=Ax^3+2Ax^2+3Ax+Bx^2+2Bx+3B
x³+ax²-(a+2)x+3a-6=Ax^3+(2A+B)x^2+(3A+2B)x+3B
A=1 2A+B=a 3A+2B=-(a+2) 3B=3a-6
A=1 B=-7/3 a=-1/3