# Matlab help

## Lab7 â€“ The Z-Transform

• Watch video entitled â€œModule 7â€“  Z-Transform in MATLABâ€
• Work the below lab assignment below using MATLAB.
• Include answers for Problems and include MATLAB coding along with any output plots that support solutions into a Word document entitled â€œLab7_StudentIDâ€.  Where your student id is substituted in the file name.

Activity 1:

A linear time-invariant discrete-time system has transfer function • Use Matlab to obtain the poles of the system. Is the system stable? Explain.
• Matlab tip: You can find the roots of a polynomial by using the roots command. For instance, if you have the polynomial x2 + 4x + 3, then you can find the roots of this polynomial as follows:

>>roots([1 4 3])

where the array is the coefficients of the polynomial.

• Compute the step response. This should be done analytically, but you can use Matlab commands like conv and residue to help you in the calculations.
• Matlab tip: Besides using conv to look at the response of a system, it can also be used to multiply two polynomials together.  For instance, if you want to know the product (x2 + 4x + 3)(x + 1), you can do the following:

>>conv([1 4 3],[1 1])

where the two arrays are the coefficients of the two polynomials.

The result is

>> ans = 1     5     7     3

Thus, the product of the two polynomials is x3 + 5x2 + 7x + 3.

Matlab tip: The command residue does the partial fraction expansion of the ratio of two polynomials. In our case, we can obtain Y(z)/z and then use the residue command to do the partial fraction expansion. Then it is relatively easy to obtain y[n] using the tables.

• Plot the first seven values of the step response. Is the response increasing or decreasing with time? Is this what you would expect, and why?

# Our guarantees

Study Acers provides students with tutoring and help them save time, and excel in their courses. Students LOVE us!No matter what kind of essay paper you need, it is simple and secure to hire an essay writer for a price you can afford at StudyAcers. Save more time for yourself. Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

### Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

### Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

### Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.