Evaluate : `cos(2cos^(-1)x+sin^(-1)x)a tx=1/5`

1.	Evaluate : `cos(2cos^(-1)x+sin^(-1)x)a tx=1/5`
Answer» `cos(2cos^-1 x + sin^-1 x) `at `x=1/5` `=> sin^-1 x + cos^-1 x = pi/2` `(cos^-1x)= sqrt(1-x^2)` `=> cos(2cos^-1 x + sin^-1x) = cos(cos^-1 x+ (cos^-1 x + sin^-1 x))` `=> cos(pi/2 + cos^-1 x) = - sin(cos^-1 x )` `= sin (cos^-1(1/5))` `= - sqrt(1- (1/5)^2)` `= sqrt(24/25) = -2sqrt6/5` Answer

Discussion

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