The domain of y = cot x is the set { x: x ∈ R and x ≠ n π, n ∈ Z } and the range is the set of all real numbers.
Numerical: If cos x = – 3 / 5, x lies in the third quadrant, find the values of other five trigonometric fx
Solution: Cos x = Base / Hypotenuse =-3 / 5 p 2 = h 2 – b 2( using Pythagoras Theorem) or p 2 = 5 2 – 3 2 or p = 4
Now, it is given that x lies in 3 rd quadrant, so sin & cos will be negative & tan will be positive.
So sin x =-4 / 5, cos x =- 3 / 5 & tan x = 4 / 3