Question

Find the value of tanθ, if cosθ = 4/5 ; 0° ≤ θ< 90°

Answer 1

• 3/4

Explanation:

Given

• cosθ = 4/5
• 0° ≤ θ < 90°

In the first quadrant both sine and cosine are positive, so as tangent.

• tanθ = sinθ / cosθ =
• 
  `√(1 - cos^2)`θ / cosθ =
• 
  `√(1 - (4/5)^2)` / 4/5 =
• 
  `√(9/25)` / 4/5 =
• 3/5*5/4 =
• 3/4