If cos θ = 4/5 then tan θ = ?
Given: cos θ = 4/5 = Base/Hypotenuse
Therefore, on comparing, Base = 4 and Hypotenuse = 5
In a right – angled triangle, (Hypotenuse)2 = (Perpendicular)2 + (Base)2
25 = (Perpendicular)2 + 16
Therefore, Perpendicular = √(25 – 16) = √(9)
= 3
Therefore tan θ = Perpendicular/Base
= 3/4