Question

Which of the following expressions is equal to ⁡tan⁡(-20°)?

tan(20°)
-tan(20°)
cot(-20°)
cot(20°)

Answer 1

The answer is -tan(20°)

Answer 2

B.
`-\text{tan}(20^(\circ))`

Explanation:

We have been given an expression
`\text{tan}(-20^(\circ))`. We are asked to find the equivalent expression to our given expression.

We know that tangent is an odd trigonometric function and it is symmetric about the origin.

A function is known as an odd function, if
`f(-x)=-f(x)` and it is symmetric with respect to origin.

Since tangent is an odd function, therefore,
`\text{tan}(-20^(\circ))=-\text{tan}(20^(\circ))` and option B i the correct choice.