Recent content by ongxom

Yes, the instruction works for the problem in my first post. But i am wondering if it works for the function like this : X(z)=\frac{4-z^{-1}}{2-2z^{-1}+z^{-2}} The numerator's lowest order is (-1), the denominator has (-2) as a lowest order. Can I multiply both numerator and denominator with...

This is the instruction from the book : But it does not say if this method can be applied for the fraction which has the order of numerator is equal or larger than denominator. Can I use the above method to find z-inverse of following fraction (order of numerator is larger and/or equal)...

Homework Statement Find inverse z-transform of X(z) = \frac{z}{(z-0.2)^2(z+0.1)} Homework Equations The Attempt at a Solution : partial fraction My method :\frac{X(z)}{z} = \frac{1}{(z-0.2)^2(z+0.1)} \frac{X(z)}{z} = \frac{-100/9}{(z-0.2)} + \frac{10/3}{(z-0.2)^2} + \frac{100/9}{z+0.1} X(z) =...

Homework Statement Write function for control system block Homework Equations The Attempt at a Solution 4 and D are parallel so we add them : I am stucking in the simplication of this block Should I group these elements to a function called w[nT], so...

Homework Statement Find the Y-parameters for the following two-port circuit Homework Equations The Attempt at a Solution Node 1 :V1(1/3+1/4)-1/4V2=I1 Node 2 : -1/4V1 + V2(1/4+1/5)-1/5(2I1)=I2 Subtitute I1 from the first equation to second equation, we have : I1=7/12V1-1/4V2...

So can we say in those cases : In an inverting op-amp, any resistors connected to the ground can be ignored when calculate ?

Yes, for the second circuit the gain is -10.

Homework Statement Find the input resistances and voltage gains for those ideal op amps Homework Equations The Attempt at a Solution The original inverting circuit look like this : we already have the equations : input resistance = 10k voltage gain = -r2/r1 = -10 For the...

Let me do it : -∞<t<-2 : No signal, 0 for amplitude. -2<t<0 : -r(t+2) is active at t=-2, -1 for amplitude. 0<t<3 : -r(t+2) and 2r(t) are both active, 2-1 for amplitude 3<t<+∞ : -r(t+2) and 2r(t) and -r(t-3) are all active, 2-1-1 for amplitude. I have no idea what the graph would look like, the...

Thank you, I got the #6. Now come to the ramp function, I have tried to separate time intervals but it seems there is nothing like the amplitude for heaviside, it doesn't work.

Another example x(t)=2u(t)-u(t-1)-u(t+1) For 2u(t) = 2 if t>0 and 0 if t<0, a line will start from (0;2) For -1u(t-1) = -1 if t>1 and 0 if t<1, line starts from (+1;-1) For -1u(t+1) = -1 if t>-1 and 0 if t<-1. line starts from (-1;-1) I tried to plot all thing above in a graph, but does not...

In the definition of unit step function, the function-2u(t-4) should be -2 if t-4>0 and 0 if t-4<0 so it should start from (4;-2), am I right ?

Let me ask some question first : Both of graph is plotted using wolframalpha, for the u-functions : y(t)=3u(t+3)-2u(t-2)-2u(t-4) The 3u(t+3) function is correct, but for -2u(t-4), i think it should have a line starts from (2;-2) but the graph only shows a line starts from (4;-1), and where is...

Only for u function Only for r function What things I have to do next to get the correct graph ?

Homework Statement Plot this signal y(t)=3u(t+3)-r(t+2)+2r(t)-2u(t-2)-r(t-3)-2u(t-4) The Attempt at a Solution I tried to draw each single function, but do not know the way to plot for the whole signal like the bottom graph