Trigonometry Examples

$\cot (\frac{- 13 π}{4})$

Step 1

Move the negative in front of the fraction.

$\cot (- \frac{13 π}{4})$

Step 2

Add full rotations of $2 π$ until the angle is greater than or equal to $0$ and less than $2 π$ .

$\cot (\frac{3 π}{4})$

Step 3

Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because cotangent is negative in the second quadrant.

$- \cot (\frac{π}{4})$

Step 4

The exact value of $\cot (\frac{π}{4})$ is $1$ .

$- 1 \cdot 1$

Step 5

Multiply $- 1$ by $1$ .

$- 1$