Question

Derive this with respect to x

`(3)/((1 + secx) )`
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Answer 1

`~~~~(d)/(dx) \left((3)/(1 + \sec x) \right)\\\\\\=3 (d)/(dx) \left( \frac 1{ 1+ \sec x} \right)\\\\\\=3 (d)/(dx) (1+ \sec x)^(-1)\\\\\\=3 (-1) (1 + \sec x )^(-1 -1) (d)/(dx)( 1 + \sec x)\\\\\\=-3(1 + \sec x)^(-2) ( 0 + \sec x \tan x)\\\\\\=-(3\sec x \tan x)/((1 + \sec x)^2)`