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Question
If a and b denote the sum of the coefficients in the expansions of \[\left( 1 - 3x + 10 x^2 \right)^n\] and \[\left( 1 + x^2 \right)^n\] respectively, then write the relation between a and b.
Solution
\[Here, \]
\[a = 1 - 3 + 10 = 8 = 2^3 \]
\[b = 1 + 1 = 2\]
\[ \Rightarrow a = b^3\]
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