Trigonometry Examples

$\tan (\frac{- 9 π}{2})$

Step 1

Rewrite $\tan (\frac{- 9 π}{2})$ in terms of sines and cosines.

$\frac{\sin (\frac{- 9 π}{2})}{\cos (\frac{- 9 π}{2})}$

Step 2

Move the negative in front of the fraction.

$\frac{\sin (\frac{- 9 π}{2})}{\cos (- \frac{9 π}{2})}$

Step 3

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

$\frac{\sin (\frac{- 9 π}{2})}{\cos (\frac{3 π}{2})}$

Step 4

Apply the reference angle by finding the angle with equivalent trig values in the first quadrant.

$\frac{\sin (\frac{- 9 π}{2})}{\cos (\frac{π}{2})}$

Step 5

The exact value of $\cos (\frac{π}{2})$ is $0$ .

$\frac{\sin (\frac{- 9 π}{2})}{0}$

Step 6

The expression contains a division by $0$ . The expression is undefined.

Undefined