JEE Main 2023 (Online) 25th January Evening ShiftQuestion 1
Let $f(x)=2x^n+\lambda$, $\lambda\in\mathbb R$, $n\in\mathbb N$, and $f(4)=133$, $f(5)=255$. Then the sum of all the positive integer divisors of $(f(3)-f(2))$ is :
Functions
Solution
$2(5^n-4^n)=122\Rightarrow n=3$, $\lambda=5$. $f(3)-f(2)=2(27-8)=38$; divisors sum $1+2+19+38=60$.