Question

y=arcsinX、arccosX、arctanX、arccotX的导数. 如题

Answer 1

都换成反函数,再用复合函数求导法.
——————————————————————
y = arcsinx
siny = x
cosy * y' = 1
y' = 1/cosy = 1/√(1 - sin²y) = 1/√(1 - x²)
——————————————————————
y = arccosx
cosy = x
- siny * y' = 1
y' = - 1/siny = - 1/√(1 - cos²y) = - 1/√(1 - x²)
——————————————————————
y = arctanx
tany = x
sec²y * y' = 1
y' = 1/sec²y = 1/(1 + tan²y) = 1/(1 + x²)
——————————————————————
y = arccotx
coty = x
- csc²y * y' = 1
y' = - 1/csc²y = - 1/(1 + cot²y) = - 1/(1 + x²)