document.write( "Question 1203631: Find A, B and C if \"A%2F%28x-1%29\" + \"B%2F%28x-2%29\" + \"C%2F%28x-3%29\" = \"%282x%5E2-6x%2B6%29%2F%28x-1%29%28x-2%29%28x-3%29\" \n" ); document.write( "
Algebra.Com's Answer #839347 by ikleyn(52781)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "Find A, B and C if \"A%2F%28x-1%29\" + \"B%2F%28x-2%29\" + \"C%2F%28x-3%29\" = \"%282x%5E2-6x%2B6%29%2F%28x-1%29%28x-2%29%28x-3%29\"
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document.write( "They want you find A, B, C from this given identity\r\n" );
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document.write( "    \"A%2F%28x-1%29\" + \"B%2F%28x-2%29\" + \"C%2F%28x-3%29\" = \"%282x%5E2-6x%2B6%29%2F%28x-1%29%28x-2%29%28x-3%29\"\r\n" );
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document.write( "This problem is, in some sense, a joking and entertainment Math problem.\r\n" );
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document.write( "Indeed, there are different ways/methods to solve it.\r\n" );
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document.write( "One way, shown by the other tutor, is direct and straightforward, but requires a lot of computations,\r\n" );
document.write( "such as reducing the problem to a system of 3 linear equations and solving this system.\r\n" );
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document.write( "This way is like a torture and can only bring tears.\r\n" );
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document.write( "But there are other ways, so beautiful that you will smile learning them.\r\n" );
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document.write( "One of such method is my solution under this link\r\n" );
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document.write( "https://www.algebra.com/algebra/homework/expressions/expressions.faq.question.1196220.html\r\n" );
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document.write( "     |     The other method I will show right here.     |\r\n" );
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document.write( "Multiply the given identity by  (x-1).  Then from the given identity (1), you will get  this identity\r\n" );
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document.write( "    A + \"B%2A%28%28x-1%29%2F%28x-2%29%29\" + \"C%2A%28%28x-1%29%2F%28x-2%29%29\" = \"%282x%5E2-6x%2B6%29%2F%28%28x-2%29%2A%28x-3%29%29\".    (2)\r\n" );
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document.write( "In this identity, place x= 1.  In its left side, you will get the second and the third addends zeroed\r\n" );
document.write( "due to presence of the factor (x-1) in the numerator. Right side of (2) at x= 1 is\r\n" );
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document.write( "    \"%282%2A1%5E2+-+6%2A1+%2B+6%29%2F%28%281-2%29%2A%281-3%29%29\" = \"%282+-6+%2B+6%29%2F%28%28-1%29%2A%28-2%29%29\" = \"2%2F2\" = 1.\r\n" );
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document.write( "Thus  A = 1.\r\n" );
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document.write( "Let's find B in similar way.  Multiply the given identity by  (x-2).  Then from the given identity (1), \r\n" );
document.write( "you will get  this identity\r\n" );
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document.write( "    \"A%2A%28%28x-2%29%2F%28x-1%29%29\" + B + \"C%2A%28%28x-2%29%2F%28x-3%29%29\" = \"%282x%5E2-6x%2B6%29%2F%28%28x-1%29%2A%28x-3%29%29\".    (3)\r\n" );
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document.write( "In this identity, place x= 2.  In its left side, you will get the first and the third addends zeroed\r\n" );
document.write( "due to presence of the factor (x-2) in the numerator. Right side of (3) at x= 2 is\r\n" );
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document.write( "    \"%282%2A2%5E2+-+6%2A2+%2B+6%29%2F%28%282-1%29%2A%282-3%29%29\" = \"%288+-12+%2B+6%29%2F%281%2A%28-1%29%29\" = \"%28-2%29%2F%28-1%29\" = -2.\r\n" );
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document.write( "Thus  B = -2.\r\n" );
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document.write( "Find C in similar way.  Multiply the given identity by  (x-3).  Then from the given identity (1), \r\n" );
document.write( "you will get  this identity\r\n" );
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document.write( "    \"A%2A%28%28x-3%29%2F%28x-1%29%29\" + \"B%2A%28%28x-3%29%2F%28x-2%29%29\" + C = \"%282x%5E2-6x%2B6%29%2F%28%28x-1%29%2A%28x-2%29%29\".    (4)\r\n" );
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document.write( "In this identity, place x= 3.  In its left side, you will get the first and the second addends zeroed\r\n" );
document.write( "due to presence of the factor (x-3) in the numerator. Right side of (4) at x= 3 is\r\n" );
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document.write( "    \"%282%2A3%5E2+-+6%2A3+%2B+6%29%2F%28%283-1%29%2A%283-2%29%29\" = \"%2818+-18+%2B+6%29%2F%282%2A1%29\" = \"6%2F2\" = 3.\r\n" );
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document.write( "Thus  C = 3.\r\n" );
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document.write( "ANSWER.  A = 1,  B = -2,  C = 3.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved as a joke Math problem.\r
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\n" ); document.write( "\n" ); document.write( "Next time, if you are given a similar functional identity of 10 addends with 10 unknown literal coefficients,
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\n" ); document.write( "\n" ); document.write( "Simply apply this method and find the coefficients one after another, independently one from another,\r
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