a^2=b^2+c^2-2bccosA
please how to proof
2007-09-29 15:00:46 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
The proof is on the attached link.
2007-09-29 15:13:57 · answer #1 · answered by gudspeling 7 · 0⤊ 0⤋
You can prove or derive this equation using dot product of vectors. See it in the book - Vector Analysis by Hwei P Hsu . It takes only about five lines.
You may also prove this graphically using trigonometry.
If ever you need it very badly, I will derive it for you and will write it on a paper and shoot it with my digicam and send it to your email. Please feel free to email me.
2007-09-29 22:13:27 · answer #2 · answered by rene c 4 · 0⤊ 0⤋
jus click on this link..
http://en.wikipedia.org/wiki/Law_of_cosines
and hope it wud be lot more informative...
2007-09-29 22:19:42 · answer #3 · answered by physics 2 · 0⤊ 0⤋