document.write( "Question 74227: What is the coefficient of x^5 in the expansion of (x+3)^8? \n" ); document.write( "

Algebra.Com's Answer #53242 by jim_thompson5910(35256) $\"\"$ $\"About$

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The binomial expansion uses Pascal's triangle to find the coefficients. The general form of the expansion (x+y)^n is
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is the coefficient. So we would use Pascals triangle to find the coefficients.
\n" ); document.write( "If you look at the 8th row of Pascal's triangle you would see
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 1     8     28    56    70    56    28    8    1

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which is to be multiplied by our terms.\r
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And we can see that 56*3^3 is our coefficient. Or in other words since our fifth term is
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our coefficient is 1512\r
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