Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 2019-12-01 14:30:39

Monox D. I-Fly
Member
From: Indonesia
Registered: 2015-12-02
Posts: 2,000

[ASK] Proving Trigonometry Identity

If

, prove that
!
All I knew is that
, but I think it doesn't help in this case.

Last edited by Monox D. I-Fly (2019-12-01 14:35:07)


Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away.
May his adventurous soul rest in peace at heaven.

Offline

#2 2019-12-01 21:43:15

Bob
Administrator
Registered: 2010-06-20
Posts: 10,052

Re: [ASK] Proving Trigonometry Identity

Are you sure this is the exact question?

From the RHS I got an expression close to the LHS but not the same.  So I tried to spreadsheet some values and did not get LHS = RHS.

eg.  If alpha = 30, beta = 60 and gamma = 90 then

LHS = 2x0.5 + 2 x root(3)/2 + 2x1 = 3  + root(3)

RHS = 4 x 0.5 x root(3)/2 x 1 = root(3)

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

Offline

#3 2019-12-02 14:24:43

Monox D. I-Fly
Member
From: Indonesia
Registered: 2015-12-02
Posts: 2,000

Re: [ASK] Proving Trigonometry Identity

Well, this was a question asked by a student I am tutoring. He did say that he tried all angles to be 60° and the equation didn't match, so I told him that it means that it couldn't be proved.


Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away.
May his adventurous soul rest in peace at heaven.

Offline

Board footer

Powered by FluxBB