document.write( "Question 987127: When z = (1+i)/(1-i), prove that z+z²+z³+z⁴=0 \n" ); document.write( "
Algebra.Com's Answer #607912 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "\"z\"\"%22%22=%22%22\"\"%281%2Bi%29%2F%281-i%29\"\"%22%D7%22\"\"%281%2Bi%29%2F%281%2Bi%29\"\"%22%22=%22%22\"\"%281%2B2i%2Bi%5E2%29%2F%281-i%5E2%29\"\"%22%22=%22%22\"\"%281%2B2i%2B%28-1%29%29%2F%281-%28-1%29%29\"\"%22%22=%22%22\"\"2i%2F2\"\"%22%22=%22%22\"\"i\"\r\n" );
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document.write( "z+z²+z³+z⁴ = i+i²+i³+i⁴ = i+(-1)+(i²×i)+(i²×i²) = i-1+(-1×i)+(-1×-1) =\r\n" );
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document.write( "i-1-i+1 = 0\r\n" );
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document.write( "Edwin
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