Question

Which angle has a cotangent value of -1?

a. Quadrant 1
b. Quadrant 2
c. 120 degrees
d. 135 degrees

Answer 1

Solution given:

cotangent x=cot x=-1

now

x=cot -¹(-1)

x=180-45°

x=135°

So

ans is d. 135 degrees.

as cot is negative in 2nd quadrant.