Answer:
When we have a rectangular point (x, y), the angle between the x-axis and a ray that connects the origin with this point is given by:
Tan(θ) = y/x.
Cos(θ) = x/(√(x^2 + y^2))
Sin(θ) = y/(√(x^2 + y^2))
So for the point (-4,3) we have:
x = -4
y = 3
√( (-4)^2 + 3^2) = √(16 + 9) = √25 = 5
Then:
Tan(θ) = 3/-4 = -(3/4)
Sin(θ) = 3/5
Cos(θ) = -4/5
And for the other 3 trigonometric functions (the inverses of the 3 above ones) we have:
Ctg(θ) = 1/Tan(θ) = -4/3
Csc(θ) = 1/Sin(θ) = 5/3
Sec(θ) = 1/Cos(θ) = -4/5
