SOLUTION: 6. find the exact value of trigonomic fucntion sec2x sin=3/5 cos=4/5

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Question 174475: 6. find the exact value of trigonomic fucntion sec2x sin=3/5
cos=4/5
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Presumably you mean that sin x = 3/5 and cos x = 4/5.

Then, cos+2x+=+2+%28cos+x%29+%5E2+-+1+
cos+2x+=+2%2A%284%2F5%29%5E2+-1+
cos+2x+=+2%2A16%2F25+-1
cos+2x+=+32%2F25+-+1
cos+2x+=+32%2F25+-+25%2F25+=+7%2F25

Now, sec+2x+=+1%2F%28cos+2x%29+=+25%2F7+

R^2