document.write( "Question 1116575: If 21st and 22nd term of the expansion (1+x)^44 are equal find the value of x
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Algebra.Com's Answer #731479 by greenestamps(13200) $\"\"$ $\"About$

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\n" ); document.write( "The first term of the expansion is

\n" ); document.write( " $\"C%2844%2C0%29%2Ax%5E0+=+1%2A1+=+1\"$

\n" ); document.write( "The n-th term of the expansion is

\n" ); document.write( " $\"C%2844%2Cn-1%29%2Ax%5E%28n-1%29\"$

\n" ); document.write( "So the 21st term is $\"C%2844%2C20%29x%5E20\"$ and the 22nd term is $\"C%2844%2C21%29x%5E21\"$ .

\n" ); document.write( "We want the two terms to be equal:

\n" ); document.write( " $\"C%2844%2C20%29x%5E20+=+C%2844%2C21%29x%5E21\"$

\n" ); document.write( " $\"x+=+C%2844%2C20%29%2FC%2844%2C21%29\"$

\n" ); document.write( " $\"x+=+%2844%21%2F%28%2820%21%29%2824%21%29%29%29%2F%2844%21%2F%28%2821%21%29%2823%21%29%29%29\"$

\n" ); document.write( " $\"x+=+%28%2821%21%29%2823%21%29%29%2F%28%2820%21%29%2824%21%29%29+=+21%2F24+=+7%2F8\"$ \n" ); document.write( "

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