[" 22."cos66^(@)+sin84^(@)=],[" (1) "(1)/(-ln sqrt(3))+sqrt(5)]

cos 66^(@) + sin 84^(@) =

Prove that 4(cos66^(@)+sin84^(@)) = sqrt(3) + sqrt(15) .

cos66^(@)+sin84^(@)=(sqrt(15)+sqrt(3))/(k) .Then k=

cos66^(0)+sin84^(0)=(sqrt(15)+sqrt(3))/(K) then K=

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

sin^(-1)(1/sqrt5)+cos^(-1)(3/sqrt(10))

sin225^(@)=sin(180^(@)+45^(@))=-sin45^(@)=-(1)/(sqrt(2)) cos246^(@)=cos(180^(@)+66^(@))=-cos66^(@)=-0.4067 tan211^(@)=tan(180^(@)+31^(@))=tan31^(@)=0.6009 .

Find the greatest & least value of f(x)=sin^(-1).(x)/(sqrt(x^(2)+1))-ln x in [(1)/(sqrt(3)), sqrt(3)] .

log(((a^(-1)sqrt(3))^((1)/(3)))/(sqrt(b^(3)sqrt(a))))

Prove that (1)cos36^(@)cos72^(@)cos108^(@)cos144^(@)=(1)/(16)(2) Show that 4sin27^(@)=sqrt(5+sqrt(5))-sqrt(3-sqrt(5))