The trigonometric expression is converted into an algebraic one, a second-order polynomial:

Roots can be found by using the General Equation for Second-Order Polynomial:

Roots are and . As tangent function has a periodicity of , solutions of and belong to first and third quadrants. Then, angles can be easily found by using inverse trigonometric functions:

## Answers ( )

Answer:or , or

Step-by-step explanation:Let use the following substitution formula:

The trigonometric expression is converted into an algebraic one, a second-order polynomial:

Roots can be found by using the General Equation for Second-Order Polynomial:

Roots are and . As tangent function has a periodicity of , solutions of and belong to first and third quadrants. Then, angles can be easily found by using inverse trigonometric functions:

or

or