NDA2015MathematicsInverse Trigonometric FunctionsActual
Consider x=4 ⁻¹ ( 1 5 ), y= ⁻¹ ( 1 70 ) and z= ⁻¹ ( 1 99 ) What is x equal to?
Options
- A⁻¹ ( 60 119 )
- B⁻¹ ( 120 119 )
- C⁻¹ ( 90 169 )
- D⁻¹ ( 170 169 )
Correct answer
B. ⁻¹ ( 120 119 )
Step-by-step solution
aligned & x=4 ⁻¹ ( 1 5 ) & =2 [2 ⁻¹ 1 5 ]=2 [ ⁻¹ 2 5 1- ( 1 5 )^2 ] & =2 ⁻¹ ( 2 5 25 24 )=2 ⁻¹ 10 24 =2 ⁻¹ 5 12 & = ⁻¹ ( 2 5 12 1- 25 144 )= ⁻¹ 120 119 . aligned