secx的导数是什么
(secx)
= (1 / cosx)
= [1cosx - (cosx)] / cos^2 x
= sinx / cos^2 x
= secxtanx
商的导数公式:
(u / v)' = [u * v^(-1)]'
= u' * [v^(-1)] + [v^(-1)]' * u
= u' * [v^(-1)] + (-1)v^(-2)*v' * u
= u' / v - u*v' / (v^2)
通分,易得
(u / v) = (u'v - uv') / v
常用导数公式:
1. c' = 0
2. x^m = mx^(m - 1)
3. sinx' = cosx,cosx' = -sinx,tanx' = sec^2x
4. a^x' = a^xlna,e^x' = e^x
5. lnx' = 1 / x,log(a,x)' = 1 / (xlna)
6. (f ± g)' = f' ± g'
7. (fg)' = f'g + fg'