Q1:

2025 Slot 3

Functions

Medium

For real values of xx, the range of the function f(x)=2x−32x2+4x−6f(x)=\frac{2x-3}{2x^2+4x-6} is

Answer options
Option 2
Correct Answer
Explanation for 2025 Slot 3 QA question 1

Q2:

2025 Slot 2

Functions

Medium

Let f(x)=x(2x−1)f(x) = \dfrac{x}{(2x-1)} and g(x)=x(x−1)g(x) = \dfrac{x}{(x-1)}. Then, the domain of the function h(x)=f(g(x))+g(f(x))h(x) = f(g(x)) + g(f(x)) is all real numbers except

Answer options
Option 2
Correct Answer
Explanation for 2025 Slot 2 QA question 2

Q3:

2025 Slot 1

Functions

Hard

Let 3≤x≤63 \leq x \leq 6 and [x2]=[x]2[x^2] = [x]^2, where [x][x] is the greatest integer not exceeding xx. If set SS represents all feasible values of xx, then a possible subset of SS is

Answer options
Option 3
Correct Answer
Explanation for 2025 Slot 1 QA question 3

Q4:

CAT 2024 Slot 3

Functions

Medium

For any non-zero real number x, let f(x)+2f(1x)=3xf(x) + 2 f(\frac{1}{x}) = 3x. Then, the sum of all possible values of xx for which f(x)=3f(x) = 3, is

Answer options
Option 4
Correct Answer
Explanation for CAT 2024 Slot 3 QA question 4

Q5:

CAT 2024 Slot 2

Functions

Hard

A function ff maps the set of natural numbers to whole numbers, such that f(xy)=f(x)f(y)+f(x)+f(y)f (xy) = f (x) f (y) + f (x) + f (y) for all x,yx, y and f(p)=1f (p) = 1 for every prime number pp. Then, the value of f(160000)f (160000) is

Answer options
Option 3
Correct Answer
Explanation for CAT 2024 Slot 2 QA question 5

Q6:

CAT 2024 Slot 1

Functions

Medium

Consider two sets A={2,3,5,7,11,13}A = \{2, 3, 5, 7, 11, 13\} and B={1,8,27}B = \{1, 8, 27\}. Let ff be a function from AA to BB such that for every element bb in BB, there is at least one element aa in AA such that f(a)=bf(a) = b. Then, the total number of such functions ff is

Answer options
Option 2
Correct Answer
Explanation for CAT 2024 Slot 1 QA question 6

Q7:

CAT 2023 Slot 3

Functions

Medium

Suppose f(x,y)f(x, y) is a real valued function such that f(3x+2y,2x−5y)=19xf(3x + 2y, 2x- 5y) = 19x, for all real numbers xx and yy. The value of xx for which f(x,2x)=27f(x, 2x) = 27, is

Q8:

CAT 2022 Slot 3

Functions

Hard

Let r be a real number and f(x)={2x−rif x≥r1if x<rf(x) = \begin{cases} 2x-r & \text{if } x \ge r \\ 1 & \text{if } x < r \end{cases}. Then, the equation f(x)=f(f(x))f(x) = f(f(x)) holds for all real values of x where.

Answer options
Option 1
Correct Answer
Explanation for CAT 2022 Slot 3 QA question 8

Q9:

CAT 2022 Slot 2

Functions

Medium

Suppose for all integers x, there are two function f and g such that f(x)+f(x−1)−1=0f(x) + f(x-1) - 1 = 0 and g(x)=x2g(x) = x^2. If f(x2−x)=5f(x^2 - x) = 5, then the value of the sum f(g(5))+g(f(5))f(g(5)) + g(f(5)) is

Q10:

CAT 2022 Slot 1

Functions

Medium

For any real number x, let [x] be the largest integer less than or equal to x. If ∑n=1N[15+n25]=25\sum_{n=1}^{N} [\frac{1}{5} + \frac{n}{25}] = 25 then N is

Q11:

CAT 2021 Slot 3

Functions

Medium

If f(x)=x2−7xf(x)=x^{2}-7 x and g(x)=x+3g(x)=x+3, then the minimum value of f(g(x))−3xf(g(x))-3 x is

Answer options
Option 1
Correct Answer
Explanation for CAT 2021 Slot 3 QA question 11

Q12:

CAT 2021 Slot 2

Functions

Medium

For all real values of x, the range of the function f(x) = x2+2x+42x2+4x+9\frac{x^2+2x+4}{2x^2+4x+9} is

Answer options
Option 2
Correct Answer
Explanation for CAT 2021 Slot 2 QA question 12

Q13:

CAT 2020 Slot 3

Functions

Easy

If f(x+y)=f(x)f(y)f(x + y) = f (x) f (y) and f(5)=4f(5) = 4, then f(10)−f(−10)f (10) - f (-10) is equal to

Answer options
Option 4
Correct Answer
Explanation for CAT 2020 Slot 3 QA question 13

Q14:

CAT 2019 Slot 2

Functions

Medium

Let ff be a function such that f(mn)=f(m)f(n)f(mn) = f(m)f(n) for every positive integers m and n. If f(1)f(1), f(2)f(2) and f(3)f(3) are positive integers, f(1)<f(2)f(1) < f(2), and f(24)=54f(24) = 54, then f(18)f(18) equals

Q15:

CAT 2019 Slot 1

Functions

Medium

Consider a function ff satisfying f(x+y)=f(x)f(y)f(\mathrm{x}+\mathrm{y})=f(\mathrm{x}) \mathrm{f}(\mathrm{y}) where x,yx , y are positive integers, and f(1)=2f(1)=2. If f(a+1)+f(a+2)+……+f(a+n)=f(\mathrm{a}+1)+f(\mathrm{a}+2)+\ldots \ldots+f(\mathrm{a}+\mathrm{n})= 16(2n−1)16\left(2^{n}-1\right) then a is equal to

Q16:

CAT 2019 Slot 1

Functions

Medium

For any positive integer nn, let f(n)=n(n+1)f(n)=n(n+1) if nn is even, and f(n)=n+3f(n)=n+3 if nn is odd. If mm is a positive integer such that 8f(m+1)−f(m)=28 f(m+1)-f(m)=2, then mm equals

Q17:

CAT 2019 Slot 1

Functions

Hard

The number of the real roots of the equation 2cos⁡(x(x+1))=2x+2−x2\cos (x(x + 1)) = 2^x + 2^{-x} is

Answer options
Option 4
Correct Answer
Explanation for CAT 2019 Slot 1 QA question 17

Q18:

CAT 2018 Slot 1

Functions

Medium

If f(x+2)=f(x)+f(x+1)f(x + 2) = f(x) + f(x + 1) for all positive integers xx, and f(11)=91f(11) = 91, f(15)=617f(15) = 617, then f(10)f(10) equals

Q19:

CAT 2017 Slot 2

Functions

Easy

Let f(x)=x2f(x) = x^2 and g(x)=2xg(x) = 2^x, for all real xx. Then the value of f(f(g(x))+g(f(x)))f(f(g(x)) + g(f(x))) at x=1x = 1 is

Answer options
Option 3
Correct Answer
Explanation for CAT 2017 Slot 2 QA question 19

Q20:

CAT 2017 Slot 2

Functions

Easy

If f(ab)=f(a)f(b)f(ab) = f(a)f(b) for all positive integers aa and bb, then the largest possible value of f(1)f(1) is

Q21:

CAT 2017 Slot 1

Functions

Medium

If f(x)=5x+23x−5f(x) = \frac{5x + 2}{3x - 5} and g(x)=x2−2x−1g(x) = x^2 - 2x - 1, then the value of g(f(f(3)))g(f(f(3))) is

Answer options
Option 1
Correct Answer
Explanation for CAT 2017 Slot 1 QA question 21