trigonometry sum
2006-06-07 21:05:51 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
a*a(cos^2 B-cos^2 C)
+b*b(cos^2 C-cos^2A)
+c*c(cos^2 A-cos^2 B)
are A,B, C angles in a triangular?
if it is, you may use the relation A+B+C=180
and cosine rule in a triangular.
2006-06-07 23:36:28 · answer #1 · answered by iyiogrenci 6 · 0⤊ 0⤋
As in prob 50 vide the adv hyperlink presented by cpmb the subject narrows all the way down to proving cosA/cosB+cosB/cosC+cosC/cosA>4(cossqA+c... by am>gm it is shown in an identical way as in prob50 that cosA/cosB+cosB/cosC+cosC/cosA >=2(cosA+cosB+cosC). so it further narrows all the way down to proving 2(cosA+cosB+cosC)>=4(cossqA+cossqB+cossq... or cosA+cosB+cosC>=2(cossqA+cossqB+cossqC) or 2(cossqA/2+cossqB/2+cossqC/2 - 3/2) >=2(cossqA+cossqB+cossqC). Now the inequality holds for any acute angled triangle the place each and each of cossqA/2-a million/2 >=cossqA for this reason proved.
2016-12-08 07:37:08 · answer #2 · answered by ? 3 · 0⤊ 0⤋
a^2(cosB^2-cosC^2)
+b^2(cosC^2-cosA^2)
+c^2(cosA^2-cosB^2)
So, what do you want to prove ?
2006-06-07 21:15:24 · answer #3 · answered by ag_iitkgp 7 · 0⤊ 0⤋
Trigonometry sum of WHAT?
Your question title is cut or incomplete.
2006-06-07 21:13:29 · answer #4 · answered by Mighty Martin 2 · 0⤊ 0⤋
I thought that was sigh language or is it baby talk?
2006-06-07 22:02:34 · answer #5 · answered by grannywinkie 6 · 0⤊ 0⤋
=a2(cos2b-cos2c)+b2(cos2b-cos2c)
2006-06-07 21:09:18 · answer #6 · answered by Rafter 2 · 0⤊ 0⤋