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View Full Version : Proving Englehorn's Equation


mintytipper
Apr 9, 2008, 03:16 PM
Prove that this is true:

(a+b)/c = (sinA + sinB)/sinC


I've been trying to manipulate the law of sines and make substitutions to the left side to get out the right side, bute I can't figure it out.

law of sines: (sinA)/a = (sinB)/b = (sinC)/c

I've been solving parts of the law of sines for the letters a, b, or c, and then putting them into the equation to attempt to get the right side out, but it just isn't working.

Help please!
Ann

iamthetman
Apr 10, 2008, 10:37 AM
Try putting everything on the right side in terms of SinA.

For example SinB = b*SinA/a and SinC = c*SinA/a and then simplify.

mintytipper
Apr 11, 2008, 05:34 PM
Thank:D you:D Thank:D you:D!!!

Now it seems so simple!!!:rolleyes:

-mintytipper:D