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帮我求下两道导函数f(x)=(5-cosx)/(5+sinx)求f'(x)f(x)=xsinx-3cosx求d^2y/dx^2

题目详情
帮我求下两道导函数
f(x)=(5-cosx) / (5+sinx) 求f '(x)
f(x)=xsinx-3cosx 求d^2y / dx^2
▼优质解答
答案和解析
1 f'(x) = [sinx*(5+sinx) - (5-cosx)*cosx]/(5+sinx)^2
= [5(sinx-cosx) +1 ]/(5+sinx)^2
2 dy/dx = sinx +xcosx +3sinx =4sinx +xcosx
d^2y / dx^2 = 4cosx + cosx -xsinx = 5cosx -xsinx