Precalculus Examples

$\tan (\frac{7 π}{2})$

Step 1

Rewrite $\tan (\frac{7 π}{2})$ in terms of sines and cosines.

$\frac{\sin (\frac{7 π}{2})}{\cos (\frac{7 π}{2})}$

Step 2

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

$\frac{\sin (\frac{7 π}{2})}{\cos (\frac{3 π}{2})}$

Step 3

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

$\frac{\sin (\frac{7 π}{2})}{\cos (\frac{π}{2})}$

Step 4

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

$\frac{\sin (\frac{7 π}{2})}{0}$

Step 5

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

Undefined