Derive Mollweide's Formula for Tangent

Is the law of tangents used at all? Our teacher never introduced it to the class.

Derive (a - b)/(a + b) = tan[(1/2)(A - B)]/tan[(1/2)(A + B)]

Also, who is Mollweide? I know that he was a mathematician but our teacher never told the class anything about this guy.

Thanks

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Originally Posted by magentarita

Is the law of tangents used at all? Our teacher never introduced it to the class.

Derive (a - b)/(a + b) = tan[(1/2)(A - B)]/tan[(1/2)(A + B)]

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what is "a" and "b" supposed to be?

Quote:

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Also, who is Mollweide? I know that he was a mathematician but our teacher never told the class anything about this guy.

Thanks

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google is your friend, and a lot of the times, wikipedia too

Our teacher placed that question on the board and walked out of the classroom.