Final answer:
The question is missing specific context for calculating E[infinity] and P[infinity] for the signal x[n] given. Typically, these terms would refer to energy and power over an infinite interval but are not standard terms. Without context, we cannot provide definitive answers, and the student should refer to their course material.
Step-by-step explanation:
The question involves determining values of E[infinity] and P[infinity] for the signal x[n]=ej(π/2)n. However, this question seems to be missing specific context or additional information that would allow for these values to be calculated. In electrical engineering and signal processing, E[infinity] typically refers to the energy of the signal over an infinite interval, and P[infinity] might refer to the power of the signal over an infinite interval. For a discrete-time signal like the one given, we would need specific definitions or formulas provided in the course material for these terms, as they are not standard terms of analysis.
If we assume that the question is asking for the total energy and power of the signal as it tends to infinity, and depending on the context, a signal like x[n] might be considered as energy-type if it is square summable, or power-type if it has a finite power. For an infinite duration complex exponential like this one, which is periodic, the total energy would typically be infinite, but the power (if defined as the average power over one period) could be finite. Again, without context, a definitive answer cannot be provided, and you should refer to your course definitions and formulas for E[infinity] and P[infinity].