SOLUTION: Use a half-angle identity to exactly evaluate the trigonometric expression: tan -3pi/8

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Question 729251: Use a half-angle identity to exactly evaluate the trigonometric expression: tan -3pi/8
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Use a half-angle identity to exactly evaluate the trigonometric expression: tan -3pi/8
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tan(-3π/8)=-tan(3π/4)/2
=-(sin3π/4)/(1+cos3π/4)
=-[√2/2/(1+(-√2/2)]
=-(√2/2)/(1-√2/2)
check with calculator:
tan(-3π/8)≈-2.4142..
-(√2/2)/(1-√2/2)≈--2.4142..