The terminal side is which defines the angle when the angle is
drawn in standard position.So, the other side is on the x-axis.
Then, you can draw a triangle with adjacent leg x = 12, opposite leg y =
5 and hypotenuse = sqrt (12^2 + 5^2 ) = 13.
So, the cosine of the angle is x-coordinate / hypotenuse = 12 / 13. That
is option b. 12 / 13.
The cotangent, is the inverse of the tangent => cot = adjacent leg /
opposite leg = x-coordinate / y-coordinate = 12/15. That is option c.
12/5. Hope this helps!
