SOLUTION: 1. tan^2 20 degree - sec^2 20 degree 2. cos^2(10 degree 5`) + sin^2 (10 degree 5`) 3. 2sec^2 2pie/7 cos^2 2pie/7

Question 697348: 1. tan^2 20 degree - sec^2 20 degree
2. cos^2(10 degree 5`) + sin^2 (10 degree 5`)
3. 2sec^2 2pie/7 cos^2 2pie/7
Answer by god2012(113) (Show Source): You can put this solution on YOUR website!
Solution :
1.

2. AMP Parsing Error of [cos^2(10 degree 5`) + sin^2 (10 degree 5`)]: Invalid function: opening bracket expected at /home/ichudov/project_locations/algebra.com/templates/Algebra/Expression.pm line 88. .
let 10 degree 5 = t
therefore, the equation becomes

3.
let 2pie/7 = t
therefore, the equation becomes

=
because sec (t) = 1/cos (t)

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