In the expansion of a x + b 2020 , if the coefficients of x 2 and x 3 are equal, then the value of 9 100 b a is equal to

Question

In the expansion of a x + b 2020 , if the coefficients of x 2 and x 3 are equal, then the value of 9 100 b a is equal to,

MARKS App · Accepted Answer

a x + b 2020 = b + a x 2020 Given, coefficient of x 2 = coefficient of x 3 ⇒ 2020 C 2 b 2018 a 2 = 2020 C 3 b 2017 a 3 ⇒ b a = 2020 C 3 2020 C 2 = 2020 ! 3 ! 2017 ! 2 ! 2018 ! 2020 ! = 2018 3 ⇒ 9 100 b a = 60 . 54

Search any question & find its solution

Looking for more such questions to practice?