Solve 0 Difference Eqn w/ Z Transform: f(k+1)-3f(k)=0, f(0)=4

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Homework Statement



Using the Z transform method, solve the difference equation:

f(k+1)-3f(k)=0, f(0)=4

Homework Equations



Z transform first shift thereom

The Attempt at a Solution



F(z)-4z-3F(z)=0

zF(z)-3F(z)=4z

F(z)*(z-3)=4z

4z/(z- 3) = f(z)

F(k) = 4 * 3^k

Providing I've done this correctly, this question seems to simple for the amount of marks given the exam papaer I pulled this from, is there anything special I need to do witht he 0 on the RHS of the equation in the original question?

Thanks
 
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the z transform of 0 is nothing! so you are in fact correct!

hope this helps!
 
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