linear approximation?
2015-12-05 7:12 am
Consider the function f(x)=x^3+2x+cosx.Use a linear approximation of f^-1(y) at y0=1 to find an approximation value of f^-1(0.98).(Hint: You may need to find x0 so that f(x0)=1)
回答 (1)
2015-12-05 2:27 pm
✔ 最佳答案
f^(-1)(0.98) (has the linear approximation) ~f^(-1)(1)+[f^(-1)]'(1)(0.98-1) using the point y0=1.As the inverse function of f(x), f^(-1) at y0=1 satisfies f^(-1)(1)=f(0)=1; and [f^(-1)]'(1)=1/[f'(0)]=1/2.
Therefore f^(-1)(0.98)~1+(-0.01)=0.99.
收錄日期: 2021-05-02 21:22:38
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20151204231202AAsxtrz