BITSAT2021MathematicsBinomial TheoremActual
Coefficient of x¹³ in the expansion of (1-x)⁵ (1+x+x²+x³ )⁴ is
Options
- A4
- B6
- C32
- D5
Correct answer
A. 4
Step-by-step solution
Expression =(1-x)⁵ (1+x)⁴ (1+x² )⁴ array l =(1-x) (1-x² )⁴ (1+x² )⁴ =(1-x) (1-x⁴ )⁴ array Coefficient of x¹³=- ⁴ C ₃(-1)³=4