How do you simplify secxtan^2x+secx?

1 Answer
Jul 15, 2016

sec x tan^2 x + sec x = sec^3 x

Explanation:

For this problem, we can use the identity

sec^2 x - 1 = tan^2 x

Rewriting our expression yields

sec x tan^2 x + sec x = sec x(sec^2 x - 1) + sec x

= sec^3 x cancel(- sec x + sec x)

= sec^3 x

We can check our answer by graphing both of them, for example.

Graph of sec x tan^2 x + sec x
graph{sec x * tan x * tan x + sec x [-28.87, 28.86, -14.43, 14.44]}
Graph of sec^3 x
graph{sec x * sec x * sec x [-28.87, 28.86, -14.43, 14.44]}