Evaluate the following: `cos(2pi)/3cospi/4-sin(2pi)/3sinpi/4`

Evaluate the following: cos(2pi/3)cos(pi/4)-sin(2pi/3)sin(pi/4)

Evaluate the following: (cos(2 pi))/(3)(cos pi)/(4)-(sin(2 pi))/(3)(sin pi)/(4)

Evaluate the following: sin(7pi)/(12)cospi/4-cos(7pi)/(12)sinpi/4

Evaluate cos (2pi/3)cos (pi/4)-sin(2pi/3)sin(pi/4)

Evaluate the following: (sin(7 pi))/(12)(cos pi)/(4)-(cos(7 pi))/(12)(sin pi)/(4)

Find the value of the following: sin^2(pi/6)+cos^2(pi/3)-tan^2(pi/4)

Evaluate the following: (i) sin^(-1)(sinpi/4) (ii) cos^(-1)(cos2pi/3) (iii) tan^(-1)(tanpi/3)

Evaluate the following: (i) sin^(-1)(sin(pi/4)) (ii) cos^(-1)(cos(2pi)/3)) tan^(-1)(tan(pi/3))

Evaluate each of the following: sin^(-1)(sin(2pi)/3) (ii) cos^(-1)(cos(7pi)/6) (iii) tan^(-1)(tan(3pi)/4)

Find the principal values of the following : (i) sin^(-1)(sin.(5pi)/(3)) (ii) cos^(-1)cos((4pi)/(3)) (iii) cos [(pi)/(3) + cos^(-1) (-(1)/(2))]