Degrees are not the only units we use to measure angles. We also use radians. Just as there are $360^\circ$ in a circle, there are $2\pi$ radians in a circle. Compute $\tan \pi,$ where the angle is in radians.
pi = 180°
On the unit circle, the terminal point of this angle can be represented by (x , y) = (-1. 0)
tan (pi) = y / x = 0 / -1 = 0
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