JEE Main 2025 Mathematics question
If in the expansion of , the coefficients of and are 1 and –2, respectively, then is equal to :
Answer: (3)
Solution
Coefficient of : . Coefficient of : solving gives , so , giving .
If in the expansion of , the coefficients of and are 1 and –2, respectively, then is equal to :
Coefficient of : . Coefficient of : solving gives , so , giving .