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--- assignments:a1 [2011/09/14 22:18] – asif
+++ assignments:a1 [2011/09/28 20:16] (current) – asif
@@ Line 24: / Line 24: @@
 Problem 1.24
+**[[http://www.cse.yorku.ca/~asif/3451fall10/HW1.pdf| Solution]] to Assignment 1 is now available.**
+**Student Questions on Assignment 1:**
+//Q1. For the assignment Problem 1.8 # (iv), how did you make exp(j(pi*k/2 + pi/8)) = 1. I don't understand this equality.//
+A1. Note that exp(j(pi*k/2 + pi/8)) does not equal 1 but the magnitude of exp(j(pi*k/2 + pi/8)) equals 1.
+Recall exp(j \theta) = cos \theta + j sin \theta
+Now, | exp(j \theta) | = sqrt (cos^2 \theta + sin^2 \theta) = sqrt (1) = 1
+//Q2. How do i Evaluate and find the period of exp(-j*pi*k).//
+A2. Note that exp(-j*pi*k) = cos(pi*k) - j sin(pi*k).
+Since sin(pi*k) = 0, therefore, exp(-j*pi*k) = cos(pi*k) which has a period of pi radians/s or 1/2 Hz.
+//Q3. If (-1^k) = exp(j*pi*k), what does (-5^k) or (5^k) equal to?//
+A3. You can not express (-5^k) or (5^k) in the form that (-1^k) was expressed.