Show that `sin^(2)5^(@)+sin^(2)10^(@)+sin^(2)15^(@)+.....+sin^(2)90^(@)=9(1)/(2)`

sin ^(2) 5 ^(@) + sin ^(2) 10 ^(@) + sin^(2) 15 ^(@) + ... + sin ^(2) 90^(@) is equal to : a) 8 (1)/(2) b) 9 c) 9 (1)/(2) d) 4 (1)/(2)

The value of sin^(2)1^(@)+sin^(2)2^(@)+sin^(2)3^(@)+....+sin^(2)88^(@)+sin^(2)89^(@) is equal to

Show that 2sin^2 (pi/6)+sin^2 (pi/4)=1

Show that sin^2 72^@ - sin^2 60^@ = (sqrt 5-1)/8

Show that cos ((pi)/(2)-x)=sin x

Show that sin ((pi)/(2)-x)=cos x

Prove that "sin"^(2)(pi)/(18)+"sin"^(2)(pi)/(9)+"sin"^(2)(7pi)/(18)+"sin"^(2)(4pi)/(9)=2 .

Prove that sin(A+B)sin(A-B)=sin^2A-sin^2B

Prove that sin ^(2) A cos ^(2) B+cos ^(2) A sin ^(2) B+cos ^(2) A cos ^(2) B+sin ^(2) A sin ^(2) B=1

Show that cos 2 x=cos ^(2) x-sin ^(2) x=2 cos ^(2) x-1=1-2 sin ^(2) x=(1-tan ^(2) x)/(1+tan ^(2) x)