SOLUTION: Use half-angle identity to find the exact value of tan 22.5 degrees

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Question 734502: Use half-angle identity to find the exact value of tan 22.5 degrees
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Use half-angle identity to find the exact value of tan 22.5 degrees
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tan 22.5º=tan(45º/2)=sin 45/(1+cos45)
=(√2/2)/(1+√2/2)
=√2/(2+√2)
..
Check with calculator:
tan 22.5º≈.4142..
√2/(2+√2)≈.4142..