I've searched online on what a graph look like in each given function and based on my online search, the given image of of the equation f(x) is a CUBIC FUNCTION.
A cubic function is like this: f(x) = ax³ + bx² + cx + d
The given graph can have this equation:
y = (x + 1) (x - 1) (x - 3)
No such thing as cot (61,4). I think you meant to say cot (61.4°). See the difference?
So, cot (61.4°) is approximately -0.139844.
Rounded to 3 decimal places we get -0.140.