JEE Main202228 Jun 2022Evening ShiftMathematicsBinomial TheoremActual
The term independent of x in the expression of 1 - x 2 + 3 x 3 5 2 x 3 - 1 5 x 2 11 , x ≠ 0 is
Options
- A7 40
- B33 200
- C39 200
- D11 50
Correct answer
B. 33 200
Step-by-step solution
General term of 5 2 x 3 - 1 5 x 2 11 is T r + 1 = C r 11 5 2 x 3 11 - r - 1 5 x 2 r = C r 11 - 1 r · 5 11 - 2 r 2 11 - r · x 33 - 5 r The term independent of x in the expansion of 1 - x 2 + 3 x 3 5 2 x 3 - 1 5 x 2 11 will be the coefficient of x 0 in 5 2 x 3 - 1 5 x 2 11 - coefficient of x - 2 in 5 2 x 3 - 1 5 x 2 11 + 3 × coefficient of x - 3 in 5 2 x 3 - 1 5 x 2 11 = - C 7 11 - 1 7 · 5 - 3 2 4 = 330 5 3 · 2 4 = 33 200