document.write( "Question 1209949: The function f : \mathbb{R} \rightarrow \mathbb{R} satisfies
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Algebra.Com's Answer #851215 by ikleyn(52788) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "The function f : R --> R satisfies
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\n" ); document.write( "\n" ); document.write( "        In his post, @CPhill derived the formula   f(x) = 2x+10   and states/claims that it is the solution to the problem.\r
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\n" ); document.write( "\n" ); document.write( "        In this my post, I will disprove his statement and will show that   f(x) = 2x+10   DOES NOT satisfy\r
\n" ); document.write( "\n" ); document.write( "        the given equation.\r
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document.write( "To check, let's take  x= 2, y= 2.\r\n" );
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document.write( "Then f(2) = 2*2+10 = 14;\r\n" );
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document.write( "so  f(x)*f(y) = f(2)*f(2) = 14*14 = 196,\r\n" );
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document.write( "    f(xy) = f(2*2) = f(4) = 2*4+10 = 18.\r\n" );
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document.write( "Therefore, the left side of the basic equation is\r\n" );
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document.write( "    f(x)*f(y) - f(xy) = 14*14 - 18 = 196 - 18 = 178.    (Left side)\r\n" );
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document.write( "The right side of the basic equation is\r\n" );
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document.write( "    -2x - 6y + 10 = -2*2 - 6*2 + 10 = -4 - 12 + 10 = -16 + 10 = -6.    (Right side)\r\n" );
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document.write( "As you see from these calculations, the left side is not equal to the right side.\r\n" );
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The conclusion is: the \"solution\" by @CPhill is a FAKE.

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\n" ); document.write( "\n" ); document.write( "Instead of to be a solution, it is an outright gibberish.\r
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