document.write( "Question 1115576: Please help me solve the following problem
\n" ); document.write( "Find all the values of z such that
\n" ); document.write( "\"exp%282z-1%29=1+\"
\n" ); document.write( "My attempt at a solution.
\n" ); document.write( "\"e%5E%282%28x%2Biy%29-1%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"e%5E%282x-1%29+%2A+e%5E%28i2y%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"e%5E%282x-1%29+%2A%28cos2y+%2Bi+sin2y%29=+1\"\r
\n" ); document.write( "\n" ); document.write( "\"e%5E%282x-1%29+%2Acos2y+%2B+e%5E%282x-1%29+%2Asin2y=+1\"\r
\n" ); document.write( "\n" ); document.write( "Pairing the real and imaginary parts gives \r
\n" ); document.write( "\n" ); document.write( "\"e%5E%282x-1%29+%2Acos2y+=+1+\" ----------- (1)\r
\n" ); document.write( "\n" ); document.write( "and\r
\n" ); document.write( "\n" ); document.write( "\"e%5E%282x-1%29+%2Asin2y+=+0+\" ----------- (2) \r
\n" ); document.write( "\n" ); document.write( "Then \r
\n" ); document.write( "\n" ); document.write( "\"sin2y=0\"\r
\n" ); document.write( "\n" ); document.write( "\"+y=+pi++\"
\n" ); document.write( "since Im trying to find a value of of y such that
\n" ); document.write( "\"+sin2y=0+\"\r
\n" ); document.write( "\n" ); document.write( "and \r
\n" ); document.write( "\n" ); document.write( "\"x=+1%2F2++\"\r
\n" ); document.write( "\n" ); document.write( "Therefore, \"+z=+1%2F2+%2B+i%28pi%29+%2B+i%282pi%29n\"
\n" ); document.write( "but the book gives the answer as \"+z=+1%2F2+%2B+i%28pi%29n\" so I know I'm messing up the imaginary part I'm just not sure how .\r
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Algebra.Com's Answer #730413 by math_helper(2461)\"\" \"About 
You can put this solution on YOUR website!
At the step sin(2y) = 0, you wrote \"+y=pi+\" but it is probably better to write \"+y+=+%28n%2Api%29%2F2+\" as potential solutions. That solves eq (2), but we need to check this solution in eq (1):\r
\n" ); document.write( "\n" ); document.write( "In solving eq (1), let n=0: \"+e%5E%282x-1%29%2Acos%282%2A%280%2Api%2F2%29%29+=+1+\" —> \"+x=1%2F2+\"
\n" ); document.write( "However, eq (1) must be checked for other values of n:
\n" ); document.write( "n=1: \"+cos%282%2A%281%2Api%2F2%29%29+=++cos%28pi%29+=+-1+\" thus n=1 is NOT a solution for eq 1
\n" ); document.write( "n=2: \"+cos%282%2A%282%2Api%2F2%29%29+=+cos%282pi%29+=+1+\" n=2 is a solution
\n" ); document.write( "n=3: \"+cos%282%2A%283%2Api%2F2%29%29+=+cos%283pi%29+=+-1+\" n=3 is NOT a solution
\n" ); document.write( "n=4: \"+cos%282%2A%284%2Api%2F2%29%29+=+cos%284pi%29+=+1+\" n=4 is a solution
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\n" ); document.write( "\n" ); document.write( "The pattern is the solution to eq (1) with \"+y=n%2Api%2F2+\" is only valid for even n:
\n" ); document.write( "Thus, the overall solution is \"+z+=+%281%2F2%29+%2B+i%2An%2Api%2F2+\" n = 0, 2, 4, 6, ….
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\n" ); document.write( "\n" ); document.write( "Which reduces to the equivalent (letting m = n/2 just to highlight this step):
\n" ); document.write( " \"+z+=+%281%2F2%29+%2B+i%2Am%2Api+\" m = 0,1,2,3,….
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