cos^(2)45^(0)+cos^(2)135^(0)+cos^(2)225^(@)+cos^(2)315^(@)

Evaluate cos^(2)45^(@)+cos^(2)135^(@)+cos^(2)225^(@)+cos^(2)315^(@) .

The value of cos^(2)75^(@)+cos^(2)45^(@)+cos^(2)15^(@)-cos^(2)30^(@)-cos^(2)60^(@) is

The value of cos^(2)75^(@)+cos^(2)45^(@)+cos^(2)15^(@)-cos^(2)30^(@)-cos^(2)60^(@) is

cos^(2)75^(0)+cos^(2)15^(0)-cos75^(0)cos15^(0)=

The value of the determinant |("sin"^(2)36^(@),"cos"^(2)36^(@),"cot"135^(@)),("sin"^(2)53^(@),"cot"135^(@),"cos"^(2)53^(@)),("cot"135^(@),"cos"^(2)25^(@),"cos"^(2)65^(@))| is

2(cos^(2) 73^(0) +cos^(2)47^(0)) - cos 154^(0) =

cos^(2)(45^(@)-alpha)+cos^(2)(15^(@)+alpha)-cos^(2)(15^(0)-alpha)=

cos ^ (2) (5 ^ (0)) + cos ^ (2) (10 ^ (0)) + cos ^ (2) (15 ^ (0)) + ...... + cos ^ (2 ) (360 ^ (@))