Question

Sandra wants to evaluate 2 cot Her work is shown below. What did she do wrong?

Answer 1

Answer: The first option.

Step-by-step explanation:

1. You need to remember that:

- An even function is a function with the following property:

f(-x)=f(x)

- An odd function  is a function with the following property:

f(-x)=-f(x)

2. By definition, the contangent is an odd function, therefore you have that:

cot(-θ)=-cot(θ)

Then:

$2cot(-\frac{9\pi}{2})\neq2cot(\frac{9\pi}{2})$

3. So, you can coclude that the first step is wrong. Therefore, the answer is the first option.