4.6c^(2)10^(@)-cot^(2)80^(@)+(sin15^(@)*cos75^(@)+cos15^(@)*sin75^(@))/(cos theta sin(90^(@)-theta)+sin theta cos(90^(@)-theta))

Find the value of sec^(2)10^(@)-cot^(2)80^(@)+(sin15^(@)cos75^(@)+cos15^(@)sin75^(@))/(costhetasin(90^(@)-theta)+sinthetacos(90^(@)-theta)) .

sin theta cos(90^(@)-theta)+cos theta sin(90^(@)-theta)

Without using Trigonometric Tables evaluate the following :- sec^2 10^@-cot^2 80^@+(sin15^@cos75^@+cos15^@sin75^@)/(costhetasin(90^@-theta)+sinthetacos(90^@-theta) .

sin theta cos(90^@ -theta) +cos theta sin(90^@ -theta) = ?

sin(270^(@)-theta).sin(90^(@)-theta)-cos(270^(@)-theta).cos(90^(@)+theta)=

((cos (90 ^ (@)) - theta) sin (90 ^ (@) - theta)) / (tan (90 ^ (@) - theta))

Prove the following: sin theta sin(90^(@)-theta)-cos theta cos(90^(@)-theta)=0

Prove the following: sin theta sin(90^(@)-theta)-cos theta cos(90^(@)-theta)=0

Without using trigonometric tables,evaluate each of the following: (sin^(2)20^(@)+sin^(2)70^(@))/(cos^(2)20^(0)+cos^(2)70^(@))+(sin(90^(@)-theta)sin theta)/(tan theta)+(cos(90^(@)-theta)cos theta)/(cot theta)+cos(40^(0)+theta)-sin(50^(@)-theta)+(cos^(2)40^(0)+cos^(2)50^(@))/(sin^(2)40^(0)+sin^(2)50^(@))

cos theta+sin theta=cos2 theta+sin2 theta