A difference equation is defined as Fn+1 =1/2Fn - 3.If the second term is 1 find the first term.

Thanks for the invitation,

Your question is not clear, but I guess you are giving a formula of elements of a sequence where n natural, right?If so, taking the second term for n=1(F2), then:1/2 F1 -3 =1 → F1=8

Let's see:

according to base formula Fn = 2(Fn+1)+6. If second term Fn+1 then first is Fn and equal to 2*1+6 = 8. Abdelbusset was right )

Thanks for the invite, I apologize for the answer, I leave the answer to the specialists.

Thank you for the invitation and leave room for specialists

F(n+1)=1/2 Fn -3

So if  F(n+1)=1 then 1=1/2 Fn -3

then Fn= 2x (1+3)= 8

Fn+1=1/2Fn-3

if R.H.S equal to 1

Fn+1=1

Fn=1-1

Fn=0

Thanks for the invite, I am not know, I am appreciate it the answer.