Answer 1

\[\frac{d}{dx}\left( 2 sec x + 3 cot x - 4 \tan x \right)\]
\[ = 2\frac{d}{dx}\left( \sec x \right) + 3\frac{d}{dx}\left( \cot x \right) - 4\frac{d}{dx}\left( \tan x \right)\]
\[ = 2 \sec x \tan x - 3 \cos e c^2 x - 4 \sec^2 x\]