SOLUTION: Please use identities and the complimentary angles to find the exact value of: 1 + tan^2 5(degrees) - csc^2 85(degrees) Thank You very much

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Question 527043: Please use identities and the complimentary angles to find the exact value of:
1 + tan^2 5(degrees) - csc^2 85(degrees)
Thank You very much

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Please use identities and the complimentary angles to find the exact value of:
1 + tan^2 5(degrees) - csc^2 85(degrees) .
**
1+tan^2(5º)-csc^2(85º)
1+(sin^2(5º))/(cos^2(5º))-1/(sin^2(85º)
Identity: sin(90º-x)=cosx
csc^2(85º)=1/sin^2(85º)
sin^2(85º)=sin^2(90º-5º)=cos^2(5º)
..
1+(sin^2(5º))/(cos^2(5º))-1/(sin^2(85º)
1+[(sin^2(5º))/(cos^2(5º))]-1/(cos^2(5º)
LCD:cos^2(5º)
[cos^2(5º)+sin^2(5º)-1]/(cos^2(5º))
Identity: cos^2(x)+sin^2(x)=1
(1-1)/cos^2(5º)=0/cos^2(5º)=0
ans:
Exact value of given function=0