`cos^(2)(theta+45^(@))+cos^(2)(theta-45^(@))=1`

cos^(2)(theta-45^(@))+cos^(2)(theta+15^(@)-cos^(2)(theta-15^(@))=

Cos (theta + 45^(@)) + Sin (theta - 45^(@)) =

What is (cos^(2)(45^(@)+theta)+cos^(2)(45^(@)-theta))/(tan(60^(@)+theta)tan(30^(@)-theta)) equal to ?

Evaluate : (cos^(2)(45^(@) + theta)+ cos^(2) (45^(@) -theta))/(tan(60^(@) + theta) xx tan(30^(@) - theta))+(cot30^(@) + sin 90^(@))xx (tan60^(@) -sec0^(@))

Evaluate : (cos^(2)(45^(@) + theta)+ cos^(2) (45^(@) -theta))/(tan(60^(@) + theta) xx tan(30^(@) - theta))+(cot30^(@) + sin 90^(@))xx (tan60^(@) -sec0^(@))

If cos theta + (1)/(cos theta) = 4 , then prove that cos^(2) theta + (1)/(cos^(2)theta) = 14.

If cos theta + (1)/(cos theta) = 4 , then prove that cos^(2) theta + (1)/(cos^(2)theta) = 14.

Prove the following identity: ((1)/(sec^(2)theta-cos^(2)theta)+(1)/(cos ec^(2)theta-sin^(2)theta))sin^(2)theta cos^(2)theta=(1-sin^(2)theta cos^(2)theta)/(2+sin^(2)cos^(2)theta)

Evaluate : (cos^(2)(45+theta)+cos^(2)(45-theta))/(tan(60^(@)+theta)tan(30^(@)-theta))+cos ec(75^(@)+theta)-sec(15^(@)-theta)