Question

If sec x = 5/3, find cos x

use reciprocal and quotient identities.
please show the work and explain simply.

Answer 1

`\sec(x)=\cfrac{5}{3}\implies \cfrac{1}{\cos(x)}=\cfrac{5}{3}\implies 3=5\cos(x)\implies \cfrac{3}{5}=\cos(x)`

mind you that secant and cosine are reciprocal of each other, so one is the other but upside-down.