JEE 2023 — Mathematics PYQ
JEE | Mathematics | 2023Let f(x)=2xn+λ,λ∈R,n∈N, and f(4)=133,f(5)=255. Then the sum of all the positive integer divisors of (f(3)−f(2)) is
Choose the correct answer:
- A.
60
(Correct Answer) - B.
59
- C.
61
- D.
58
60
Explanation
Solving
1. Finding n
Using the given values:
Subtracting the two equations to eliminate λ:
By inspection/trial:
-
If n=1: 5−4=1=61
-
If n=2: 25−16=9=61
-
If n=3: 125−64=61
So, n=3.
2. Calculating (f(3)−f(2))
The expression for (f(3)−f(2)) is:
Substitute n=3:
3. Finding the sum of divisors of 38
The prime factorization of 38 is:
The divisors of 38 are: 1,2,19,38.
Sum of divisors:
Correct Option: (1)
Explanation
Solving
1. Finding n
Using the given values:
Subtracting the two equations to eliminate λ:
By inspection/trial:
-
If n=1: 5−4=1=61
-
If n=2: 25−16=9=61
-
If n=3: 125−64=61
So, n=3.
2. Calculating (f(3)−f(2))
The expression for (f(3)−f(2)) is:
Substitute n=3:
3. Finding the sum of divisors of 38
The prime factorization of 38 is:
The divisors of 38 are: 1,2,19,38.
Sum of divisors:
Correct Option: (1)

