`Cos^2 (52 1/2)-sin^2 (22 1/2)`

sin^2 52 1/2^@-cos^2 7 1/2^@

sin ^ (2) 52 (1) / (2) -sin ^ (2) 22 (1) / (2) =

cos [cos^(-1)(-1/2)-sin^(-1)(1/2)]

cos^(-1)(1-2sin^(2)x)

Find the value of cos^(2)112(1)/(2^(@))-sin^(2)52(1)/(2^(@))

The value of sin ( 67 (1_@)/2 ) sin ( 22 (1_@)/2) is

cos A=cos^(2)((A)/(2))-sin^(2)((A)/(2))=1-2sin^(2)((A)/(2))=2cos^(2)((A)/(2))-1

The value of 2cos^(-1)(-1/2)-2 sin^(-1)(-1/2)-cos^(-1)(-1) is

Prove that: ((1) / (sec ^ (2) A-cos ^ (2) A) + (1) / (cos ec ^ (2) A-sin ^ (2) A)) sin ^ (2) A cos ^ (2) A = (1-sin ^ (2) A cos ^ (2) A) / (2 + sin ^ (2) A cos ^ (2) A)

((1) / (sec ^ (2) A-cos ^ (2) A) + (1) / (cos ec ^ (2) A-sin ^ (2) A)) sin ^ (2) A cos ^ (2) A = (1-sin ^ (2) A cos ^ (2) A) / (2 + sin ^ (2) A cos ^ (2) A)