Question #e1f68 Trigonometry Inverse Trigonometric Functions Basic Inverse Trigonometric Functions 2 Answers P dilip_k Dec 26, 2016 sin(tan^-1u+sin^-1v)sin(tan−1u+sin−1v) =sin(cot^-1(1/u)+sin^-1v)=sin(cot−1(1u)+sin−1v) =sin(csc^-1sqrt(1+1/u^2)+sin^-1v)=sin(csc−1√1+1u2+sin−1v) =sin(csc^-1((sqrt(u^2+1))/u)+sin^-1v)=sin(csc−1(√u2+1u)+sin−1v) =sin(sin^-1(u/(sqrt(u^2+1)))+sin^-1v)=sin(sin−1(u√u2+1)+sin−1v) =sinsin^-1((u/(sqrt(u^2+1)))xxsqrt(1-v^2)+sqrt(1-u^2/(u^2+1))xxv)=sinsin−1((u√u2+1)×√1−v2+√1−u2u2+1×v) =((usqrt(1-v^2))/(sqrt(u^2+1))+v/sqrt(u^2+1))=(u√1−v2√u2+1+v√u2+1) =(usqrt(1-v^2)+v)/sqrt(u^2+1)=u√1−v2+v√u2+1 Answer link A. S. Adikesavan Dec 26, 2016 =(u sqrt(1-v^2)+v)/sqrt(1+u^2)=u√1−v2+v√1+u2 Explanation: Let a = tan^(-1)u in Q_1, if u >= 0, and in Q_2 if u <= 0. sin a = u/sqrt(1+u^2) and cos a= 1/sqrt(1+u^2) Let b = sin^(-1)v in Q_1, if v >= 0, and in Q_2 if v <= 0. sin b = v and cos v = sqrt(1-v^2) In any case, cos a and cos b > 0. sin a < 0, if u < 0. The given expression is sin ( a + b ) = sin a cos b + cos a sin b =(u/sqrt(1+u^2))(sqrt(1-v^2))+(1/sqrt(1+u^2))(v) =(u sqrt(1-v^2)+v)/sqrt(1+u^2) Answer link Related questions What are the Basic Inverse Trigonometric Functions? How do you use inverse trig functions to find angles? How do you use inverse trigonometric functions to find the solutions of the equation that are in... How do you use inverse trig functions to solve equations? How do you evalute sin^-1 (-sqrt(3)/2)? How do you evalute tan^-1 (-sqrt(3))? How do you find the inverse of f(x) = \frac{1}{x-5} algebraically? How do you find the inverse of f(x) = 5 sin^{-1}( frac{2}{x-3} )? What is tan(arctan 10)? How do you find the arcsin(sin((7pi)/6))? See all questions in Basic Inverse Trigonometric Functions Impact of this question 2267 views around the world You can reuse this answer Creative Commons License