What's the cot (180°) + (cos (180°) / sin (180°))

the answer is 'undefined'

Step-by-step explanation:

Cot is defines as (cos x) / (sin x)

So we can rewrite our expression as ...

(cos 180°) / (sin 180°) + (cos 180°) / (sin 180°)

or

2 (cos 180°) / (sin 180°)

Cos 180° = 1, sin 180° = 0 (you get these from the unit circle)

so we have

2 (1/0) = 2/0, which is undefined, because we don't divide by zero