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# C2 trigonometry

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1. The question is:

'Find the two possible triangles ABC which satisfy b=5, a=3, A=35' '

I found the first triangle, where B=72.9', C=72.1' and c=4.98. How do I find the other one?
2. The angle B can have two values, because sin(B) = sin(180-B)
Let Beta = 180 - B.
Your second triangle has an angle Beta, say, rather than B, and still have the same characteristics as the triangle with an angle = B.
3. (Original post by steve10)
The angle B can have two values, because sin(B) = sin(180-B)
Let Beta = 180 - B.
Your second triangle has an angle Beta, say, rather than B, and still have the same characteristics as the triangle with an angle = B.
Ohhh, I see. Thank you.
4. Couldn't you use the cosine rule? Or is there not enough data ? :P

Or even the sine rule?

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Updated: May 17, 2012
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