# Fibonacci sequence

• November 3rd 2012, 11:14 AM
TABASSUM
Fibonacci sequence
Hi can anyone explain how i can get express Fn+3 in terms of Fn+2 and Fn to show that Fn+2 = 1/2(Fn+3 + Fn). Any help is much appreciated
• November 3rd 2012, 12:21 PM
MarkFL
Re: Fibonacci sequence
I would begin with:

(1) $F_{n+2}=F_{n+1}+F_{n}$

(2) $F_{n+3}=F_{n+2}+F_{n+1}$

Now, solve (2) for $F_{n+1}$ and substitute into (1), then solve for $F_{n+2}$.
• November 3rd 2012, 03:57 PM
TABASSUM
Re: Fibonacci sequence
Thankyou so much.