Prove that `tan ((3pi)/11) + 4 sin ((2pi)/11)=sqrt( 11)`.

tan((11pi)/12)

sin((-11pi)/3)

Prove that: tan(pi/4+A). Tan((3pi)/4)+A=-1

Prove that : tan\ pi/7*tan\ (2pi)/7*tan\ (3pi)/7=sqrt(7)

Prove that: sin(pi/14)sin((3pi)/14)sin((5pi)/14)sin((7pi)/14)sin((9pi)/14)sin((11pi)/14)sin((13pi)/14)=1/(64)

Prove that sin ""(pi)/(9) sin ""(2pi)/(9) sin ""( 3pi)/(9) sin ""(4pi)/(9) = (3)/(16).

Prove that: i) sin(5pi)/(18) - cos(4pi)/(9) = sqrt(3)sinpi/9 ii) cos(3pi)/4+A-cos((3pi)/(4)-A)=-sqrt(2)sinA

prove that : sin((5pi)/18)-cos((4pi)/9)=sqrt(3)sin(pi/9)

prove that : cos(pi/12)-sin(pi/12)=1/(sqrt(2))

Prove that : tan((11pi)/3)-2sin((9pi)/3)-3/4cosec^2(pi/4)+4cos^2((17pi)/6)=(3-2sqrt(3))/2