F(n)=11/2n-8

Solution for F(n)=11/2n-8 equation:

(F)=11/2F-8

We move all terms to the left:

(F)-(11/2F-8)=0


Domain of the equation: 2F-8)!=0

F∈R


We get rid of parentheses

F-11/2F+8=0

We multiply all the terms by the denominator


F*2F+8*2F-11=0

Wy multiply elements

2F^2+16F-11=0

a = 2; b = 16; c = -11;
Δ = b2-4ac
Δ = 162-4·2·(-11)
Δ = 344
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$F_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{344}=\sqrt{4*86}=\sqrt{4}*\sqrt{86}=2\sqrt{86}$
$F_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-2\sqrt{86}}{2*2}=\frac{-16-2\sqrt{86}}{4}
$
$F_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+2\sqrt{86}}{2*2}=\frac{-16+2\sqrt{86}}{4}
$