COMEDK · Maths · 7. Binomial Theorem
If the sum of the coefficients of the first three terms in the expansion of \(\left(x-\dfrac{a}{x^2}\right)^{12}, x \neq 0\) is 559. Find the value of '\(a\)' if '\(a\)' belongs to positive integers
- A 3
- B 4
- C \(\dfrac{31}{11}\)
- D 5
Answer & Solution
Correct Answer
(A) 3
Step-by-step Solution
Detailed explanation
The expansion of \(\left(x - \dfrac{a}{x^2}\right)^{12}\) is given by the binomial theorem as \(\sum_{r=0}^{12} {^{12}C_{r}} (x)^{12-r} \left(-\dfrac{a}{x^2}\right)^{r}\). The first three terms correspond to \(r=0, 1, 2\). For \(r=0\): Term is…
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