f(x)=ax^3-13x^2+bx-60除以3x^2-14x-5时,余式是7x-35,求a和b._数学解答

f(x)=ax^3-13x^2+bx-60除以3x^2-14x-5时,余式是7x-35,求a和b.

人气：489 ℃　时间：2020-03-27 01:00:59

解答

该体为待定系数,设原式=(3x^2-14x-5)(cx加d)=3cx^3加(3d-14c)x^2加(-14d-5c)x-5d则对应项相等,-5d=-60-(-35);3d-14=-13解得c=2;d=5则a=3c=6;b=7-14d-5c=-73