SOLUTION: Question: If tan\theta =5/12, 0<=theta <=90, then cos theta = ? My answer: Tan = Sin/Cos and therefore cos = 12. I am wrong per the answer in the book. Can someone please

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Question 1172059: Question: If tan\theta =5/12, 0<=theta <=90, then cos theta = ?
My answer: Tan = Sin/Cos and therefore cos = 12.
I am wrong per the answer in the book. Can someone please explain to me why am I wrong. The answer in the book is 12/5 which seems to be the inverse of the tan!
Thank you
Answer by math_helper(2461) (Show Source):
You can put this solution on YOUR website!

You can sanity check your answer by remembering , so clearly neither 12 nor 12/5 can be correct. This is true for sin(x) as well, but not true for tan(x).

It is often best to draw a triangle for these types of problems.

..... opp/adj

..... adj/hyp
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Just thought to add this, as you might find it helpful.

..... opp/hyp
So, for this problem, = = =