SOLUTION: Use properties of the trigonometric functionS to find the exact value of sec^2 18 -tan^2 18

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Question 707360: Use properties of the trigonometric functionS
to find the exact value of sec^2 18 -tan^2 18
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Use properties of the trigonometric functionS
to find the exact value of sec^2 18 -tan^2 18
**
Pythagorean Identity:
tan^2x+1=sec^2x
sec^2x-tan^2x=1
so,
sec^2 18 -tan^2 18=1