document.write( "Question 1209317: Let f be a function such that
\n" ); document.write( "f(x+y) = x + f(y) + f(y^2) - y^2
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Algebra.Com's Answer #848307 by mccravyedwin(407)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Now if you want to change the problem so that f(0) = 0, not -5,\r\n" );
document.write( "then:\r\n" );
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document.write( "       f(x+y) = x + f(y) + f(y^2) - y^2\r\n" );
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document.write( "Let x = -1 and y = 1\r\n" );
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document.write( "      f(-1+1) = -1 + f(1) + f(1^2) - 1^2\r\n" );
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document.write( "         f(0) = -1 + f(1) + f(1) - 1\r\n" );
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document.write( "            0 = 2f(1) - 2\r\n" );
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document.write( "            2 = 2f(1) \r\n" );
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document.write( "         f(1) = 1\r\n" );
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document.write( "Edwin
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