Question

求在曲线y=x^3+x-1上求一点P,使在点P处的切线与直线y=4x-7平行的答案.

Answer 1

y'=3x²+1

设P(x0,y0)

y'|x=x0 =3x0²+1=4

x0²=1

x0=1或x0=-1

(1) x0=1,y=1,P(1,1)

(2) x0=-1,y=-3,P(-1,-3)