NDA2022MathematicsBinomial TheoremActual
Paragraph: Consider the binomial expansion of (p+q x)^9 : Question: What is the value of q if the coefficients of x^3 and x^6 are equal ?
Options
- Ap
- B9 p
- C1 p
- Dp^2
Correct answer
A. p
Step-by-step solution
Given expansion is (p+q x)^9T^ r +1 = ^9 Cr p^ 9- r (q x)^ r = ^9 Cr p p^ q - r q^ r x^ r coefficient of x^3= coefficient x^6 aligned & ^9 C₃ p^6 q^3= ^9 C₆ p^3 q^6 & p^3=q^3 & p=q aligned