" (iii) "cos15^(@)-sin15=(1)/(sqrt(2))

Prove that (i) " 2 cos " 45^(@) " cos " 15^(@)=((sqrt(3)+1))/(2) " "(ii) 2 " sin " 75^(@) " sin " 15^(@)=(1)/(2) (iii) " cos " 15^(@) - " sin " 15 =(1)/(sqrt(2))

Prove that cos 15 ^(@) - sin 15^(@) = (1)/(sqrt2)

Prove that : (i) "sin"105^(@)+cos105^(@)=(1)/(sqrt(2)) (ii) cos105^(@)+cos15^(@)="sin"75^(@)-"sin"15^(@)

Prove : cos15^(@) - sin15^(@) = 1//sqrt2 .

Prove that: cos15^@-sin15^@=1/sqrt2

Prove that (i) "cos " 15^(@) - " sin " 15^(@) = (1)/(sqrt(2)) (ii) " cot " 105^(@) - " tan " 105^(@) =2sqrt(3) (iii) (tan 69^(@) + tan 66^(@))/(1-tan 69^(@) tan 66^(@)) =-1

(cos15^(@)+sin15^(@))/(cos15^(@)-sin15^(@))=(i)1(ii)sqrt(3)(iii)(1)/(sqrt(3))(iv)2+sqrt(3)

Evaluate ((cos15^(@)-sin15^(@)+1)/(cos15^(@)+sin15^(@)+1))((1+sin15^(@))/(cos15^(@)))

(sin 75^(@) - sin 15 ^(@))/( cos 75^(@) + cos 15 ^(@)) = (1)/(sqrt3)