(a) Write a Matlab function signalx that evaluates the following signal at an arbitrary set of points:
x(t) = ∫ 2e^ t+2, −3 <_ t <_ −1
2e^−t cos 2πt, −1 <_ t <_ 4
0, else
That is, given an input vector of time points, the function should give an output vector with the values of x evaluated at those time points. For time points falling outside [−3, 4], the function should return the value zero.
(b) Use the function signalx to plot x(t) versus t, for −6 <_ t <_ 6. To do this, create a vector of sampling times spaced closely enough to get a smooth plot. Generate a corresponding vector using signalx. Then plot one against the other.
(c) Use the function signalx to plot x (t − 3) versus t.
(d) Use the function signalx to plot x (3 − t) versus t.
(e) Use the function signalx to plot x (2t) versus t.