Zaymiey

📐 Mathematics  ·  Inverse Trigonometric Functions  ·  JEE

The value of sin(2·arctan(3/4)) is:

Answer: 24/25.

  • A 24/25
  • B 7/25
  • C 12/25
  • D 3/5

Correct answer: A. 24/25

Explanation: With tanθ = 3/4, sin2θ = 2tanθ/(1 + tan²θ) = (3/2)/(25/16) = 24/25.

y = sin⁻¹x: Principal Value Branchxyx=-1x=1y=-π/2y=π/2Domain restricted to [-1,1]; range restricted to [-π/2,π/2] - this restriction is what makes the inverse exist

The graph of sin⁻¹x is confined to a narrow domain [-1,1] (since sine itself only takes values in that range) and range [-π/2,π/2] (the principal value branch chosen to make sine one-one and invertible there).

Concept context

Restricting trig functions to make them invertible, the principal value branches of sin-inverse, cos-inverse, tan-inverse, and friends, and the key identities relating them.

Read the full Inverse Trigonometric Functions notes →