JEE Main 2025MathematicsBinomial TheoremMediumMCQ

JEE Main 2025Binomial Theorem Question with Solution

JEE Main 2025 (28 Jan Shift 2)

Question

Let the coefficients of three consecutive terms and in the binomial expansion of be in a G.P. and let be the number of all possible values of . Let be the sum of all rational terms in the binomial expansion of . Then is equal to :

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Correct answer
A

Step-by-step explanation

Coefficient of $\begin{aligned} & T_r, T_{r+1}, T_{r+2} \rightarrow G P \\ & \Rightarrow\left({ }^{12} C_r\right)^2={ }^{12} C_{r-1} \cdot{ }^{12} C_{r+1} \end{aligned}$ but no three consecutive binomial coefficient are in GP Now for for rational terms sum of rational terms $\begin{aligned} & ={ }^{12} \mathrm{C}_0 4^0 \cdot 3^3+{ }^{12} \mathrm{C}_{12} \cdot 4^4 \cdot 3^0 \\ & =27+256=283=q \\ & \therefore p+q=283 \end{aligned}$

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About this question

This is a previous-year question from JEE Main 2025, covering the Binomial Theorem chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.