sin^(2)11(1)/(4)+cos^(4)11(1)/(4)=

cos ((5pi)/(4)) - sin ((5pi)/(4)) + tan((11pi)/(4)) - cot((11pi)/(4))=

Find "sin" 7(1^(@))/(2),cos 7(1^(@))/(2) and "tan" 11(1^(@))/(4) .

Simplify : (11^((1)/(2)))/( 11^((1)/(4)))

Prove that cos^(-1)(3/11)-sin^(-1)(3/4)=sin^(-1)(19/44)

let x_(1)=cos((pi)/(11))cos((2 pi)/(11))cos((3 pi)/(11))cos((4 pi)/(11))cos((5 pi)/(11)) and x_(2)=cos((pi)/(11))+cos(2(pi)/(11))+cos(3(pi)/(11))+cos(4(pi)/(11))+cos(5(pi)/(11)) then show that x_(1).x_(2)=(1)/(64)(cos ec((pi)/(22))-1)

Find the value of (cos^(4)1^(@)+cos^(4)2^(@)+cos^(4)3^(@)+......+cos^(4)179^(@))-(sin^(4)1^(@)+sin^(4)2^(@)+sin^(4)3^(@)+.......+sin^(4)179^(@)) .

Prove that : cos^(-1).(4)/(5)+ tan ^(-1).(3)/(5) = tan^(-1) .(27)/(11) (ii) Prove that : sin^(-1).(3)/(5)+ tan ^(-1).(3)/(5) = tan^(-1) .(27)/(11)

If (sin^(-1)x)^2 – (cos^(-1) x)^2 = api^2 then the range of 'a' is a) [-3/4,1/4] b) [-3/4,3/4] c) [-1,1] d) [-1,3/4]