Question 16
Binomial TheoremFind the coefficient of the 6th term in ascending powers of x in the binomial expansion of (1 − 3x/4)9
- A.−15309/512
- B.−15309/256
- C.−5103/512
- D.−5103/256
Show the answer and explanation
Answer: A (−15309/512)
Explanation
The 6th term is ⁹C₅(−3x/4)⁵ = 126 × (−243/1024)x⁵, and 126 × 243/1024 = 15309/512, so the coefficient is −15309/512.