# Choose the correct answer in each of the following questions: cos^(2)30^(@)cos^(2)45^(@)+4sec^(2)60^(@)+(1)/(2)cos^(2)90^(@)-2tan^(2)60^(@)=?

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Choose the correct answer in each of the following questions:
cos^(2)30^(@)cos^(2)45^(@)+4sec^(2)60^(@)+(1)/(2)cos^(2)90^(@)-2tan^(2)60^(@)=?
A. (73)/(8)
B. (75)/(8)
C. (81)/(8)
D. (83)/(8)

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cos^(2)30^(@)cos^(2)45^(@)+4sec^(2)60^(@)+(1)/(2)cos^(2)90^(@)-2tan^(2)60^(@)
=((sqrt(3))/(2))^(2)*((1)/(sqrt(2)))^(2)+(4xx2^(2))+((1)/(2)xx0^(2))-2xx(sqrt(3))^(2)
=((3)/(4)xx(1)/(2))+16+0-6=(3)/(8)+10=(83)/(8).