Question:medium
The number \(81\) is the coefficient of \( x^k \) in the binomial expansion of \( \left(x^2 + \frac{3}{x}\right)^4 \), \( x \neq 0 \). Then the value of \( k \) equals
The number \(81\) is the coefficient of \( x^k \) in the binomial expansion of \( \left(x^2 + \frac{3}{x}\right)^4 \), \( x \neq 0 \). Then the value of \( k \) equals
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Always match BOTH coefficient and power when identifying a term.
Updated On: Apr 30, 2026
- \(-2\)
- \(2\)
- \(-4\)
- \(4\)
- \(5\)
Show Solution
The Correct Option is C
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