F(x)

par **Branza** » 30 Aoû 2008, 11:18

i have another problem and i thought it but without results,if u can help me?
f(x)=???
if:
f(2x+3)-2f(x-2)=26
i try to solve it but i cant,i determined one point:f(-7)=-26,but i need another point to solve the probleme.
i forggot to precise that f had form:ax+b.

par **Euler911** » 30 Aoû 2008, 11:27

Hello,

If f(x)=ax+b, f(2x+3)=a(2x+3)+b, ...f(x-2)=...

Then f(2x+3)-2f(x-2)= .................=26

So...

par **Clembou** » 30 Aoû 2008, 12:27

Euler911 a écrit:Hello,

If f(x)=ax+b, f(2x+3)=a(2x+3)+b, ...f(x-2)=...

Then f(2x+3)-2f(x-2)= .................=26

So...

So what ? I don't understand your help :triste:

par **Doraki** » 30 Aoû 2008, 12:30

since you only considers affine functions, the equation you're given is equivalent to what you found, f(-7) = -26.
So there are infinitely many solutions, which are the equations of the lines going through that point (-7,-26).

par **Euler911** » 30 Aoû 2008, 12:34

Clembou a écrit:So what ? I don't understand your help :triste:

You don't have to understand my help you know... But if you think I wrote sth wrong, you can tell me.

par **_-Gaara-_** » 30 Aoû 2008, 13:25

Funny one :we:

F(x)

f(x)

Qui est en ligne