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प्रश्न
If a and b denote respectively the coefficients of xm and xn in the expansion of \[\left( 1 + x \right)^{m + n}\], then write the relation between a and b.
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उत्तर
\[\text{ Coefficient of } x^m \text{ in the given expansion } = ^t{m + n}{}{C}_m = a\]
\[\text{ Coefficient of } x^n \text{ in the given expansion } = ^{m + n}{}{C}_n = b\]
\[ \therefore a = b \left[ \because^{m + n}{}{C}_m = ^{m + n}{}{C}_n \right]\]
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