Question:

The number of real roots of the equation 3⁹C₃r-1-3⁹Cᵣ²=3⁹Cᵣ²-1-3⁹C₃r is

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Cancel common combination terms carefully.

Updated On: Mar 19, 2026

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The Correct Option is B

Solution and Explanation

Using properties of combinations and simplifying gives: r(3r-1)=r²(3r-1) ⟹ r=0,1

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