JEE Main202427 Jan 2024Morning ShiftMathematicsBinomial TheoremActual
If A denotes the sum of all the coefficients in the expansion of 1 - 3 x + 10 x 2 n and B denotes the sum of all the coefficients in the expansion of 1 + x 2 n , then :
Options
- AA = B 3
- B3 A = B
- CB = A 3
- DA = 3 B
Correct answer
A. A = B 3
Step-by-step solution
We have, A = Sum of the coefficients in the expansion of ⇒ 1 - 3 x + 10 x 2 n = ( 1 - 3 + 10 ) n = ( 8 ) n = ( 2 ) 3 n (putting x = 1 ) Now, B = Sum of the coefficients in the expansion of ⇒ 1 + x 2 n = ( 1 + 1 ) n = 2 n Clearly, A = B 3 .