Question

Tan40*cot50-sec40*csc50

I know the answer is -1, but I'm not sure how to get it.

Answer 1

`\tan 40^(\circ) \cot 50^(\circ)-\sec 40^(\circ) \csc 50^(\circ)\\\\=\tan 40^(\circ) \tan 40^(\circ)-\sec 40^(\circ) \sec 40^(\circ)\\\\=\tan^2 40^(\circ)-\sec^2 40^(\circ)\\\\=-1`