Question

I need to find the f'''(x) of sec x

Answer 1

So, would that be the derivative of tan(x)sec(x) ?

Answer 2

if so, you can just use the product rule gf' + fg'

Answer 3

That's f'3(x)

Answer 4

The first one is tanxsecx
the second one is = \[\tan ^2 x secx+\sec3 x\]

Answer 5

http://www.wolframalpha.com/input/?i=derivative+of+(tanx)^2+*+secx%2Bsec3x this may help