If A denotes the sum of all the coefficients in the expansion of $\left(1-3 x+10 x^2\right)^{\mathrm{n}}$ and B denotes the sum of all the coefficients in the expansion of $\left(1+x^2\right)^n$, then :
Solution
<p>Sum of coefficients in the expansion of $\left(1-3 \mathrm{x}+10 \mathrm{x}^2\right)^{\mathrm{n}}=\mathrm{A}$</p>
<p>then $A=(1-3+10)^n=8^n$ (put $x=1$)<?p>
<p>and sum of coefficients in the expansion of</p>
<p>$$\begin{aligned}
& \left(1+x^2\right)^n=B \\
& \text { then } B=(1+1)^n=2^n \\
& A=B^3
\end{aligned}$$</p>
About this question
Subject: Mathematics · Chapter: Binomial Theorem · Topic: Binomial Expansion
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