document.write( "Question 1022124: Please help , add 2C1 + 2C2 + 3C2 expressing your answer as a single binomial coefficient.Thanks in advance. \n" ); document.write( "
Algebra.Com's Answer #637856 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Learn how Pascal's triangle of binomial coefficients\r\n" );
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document.write( "If we add any two numbers which are side by side, we \r\n" );
document.write( "will always get the number which is between and below \r\n" );
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document.write( "                        0C0=1\r\n" );
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document.write( "                  1C0=1      1C1=1       \r\n" );
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document.write( "              2C0=1     2C1=2     2C2=1\r\n" );
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document.write( "         3C0=1    3C1=3      3C2=3     3C3=1\r\n" );
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document.write( "    4C0=1     4C1=4     4C2=6     4C3=4     4C4=1  \r\n" );
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document.write( "2C1 + 2C2 + 3C2\r\n" );
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document.write( "Add just the first two:\r\n" );
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document.write( "If we add 2C1=2 and 2C2=1, they are side by side, so we\r\n" );
document.write( "get the number between and below them which is 3C2=3.\r\n" );
document.write( "Then if we add 3C2 to that we get 2(3C2)=6.\r\n" );
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document.write( "Then we notice that 4C2 also = 6, and 4C2 is a single\r\n" );
document.write( "binomial coefficient, so the answer is 4C2.\r\n" );
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document.write( "Edwin
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