`sin^2 17. 5^(@)+sin^2 72. 5^(@)` is equal to

sin^(2)5^(@) + sin^(2)25^(@) + sin^(2)45^(@) + sin^(2) 65^(@) + sin^(2) 85^(@) is equal to:

cos^(2)(97.5^(@))-sin^(2)(37.5^(@)) is equal to-

sin^(2)5^(@)+sin^(2)10^(@)+sin^(2)15^(@)+ .....+sin^(2)85^(@)+sin^(2)90^(@) is equal to

The value of sin^(2)5^(@)+sin^(2)10^(@)+sin^(2)15^(@)+ . . . .+sin^(2)90^(@) is equal to

The value of (cos ^(6)5^(@)-15 cos ^(4) 5^(@) sin ^(2)5^(@)+15 cos ^(2)5^(@)sin ^(4) 5^(@)-sin ^(6)5^(@)) is equal to-

sin18^(@)-cos72^(@) is equal of :

sin ^ (2) 17.50 + sin ^ (2) 72.50

cos 72^@ - sin18^@ is equal to

(sin^2 1^@ + sin^2 3^@ + sin^2 5^@ + ………………… + sin^2 85^@ + sin^2 87^@ + sin^2 89^@) equals____

Prove that sin ^(2) 72 ^(@)- sin ^(2) 60 ^(@)= (sqrt5-1)/(8).