Math Is Fun Forum

Monox D. I-Fly

Member

From: Indonesia

Registered: 2015-12-02

Posts: 2,000

[ASK] Prove

Prove that

. Can someone provide me some hints? I tried to manipulate the right-hand expression but got back to square one.

---

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.

George,Y

Member

Registered: 2006-03-12

Posts: 1,379

Re: [ASK] Prove

https://www.mathsisfun.com/algebra/trigonometric-identities.html

---

X'(y-Xβ)=0

Bob

Administrator

Registered: 2010-06-20

Posts: 10,626

Re: [ASK] Prove

hi

Get a similar expression for sin(A+B) - sin(A-B).

Let A = x+y and B = x-y

Convert the LHS using these and simplify.

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

Monox D. I-Fly

Member

From: Indonesia

Registered: 2015-12-02

Posts: 2,000

Re: [ASK] Prove

Well, I got this:

=

=

= cot(x - y) =

Last edited by Monox D. I-Fly (2019-12-01 18:41:01)

---

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.