Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main 202429 JanuaryMorning Shift
Exam
JEE Main
Year
2024
Date
29 January
Shift
Morning Shift
Subject
Mathematics
Chapter
Functions

JEE Main 2024 · 29 January · Morning Shift · Mathematics · Functions

If f(x) = \ array ll 2 + 2x, - 1 ≤ x < 0 1 - (x)/(3), 0 ≤ x ≤ 3...

If f\left(x\right) = \left\{2+2x,−1≤x<01−x3,0≤x≤3\begin{array}{ll}2 + 2x, - 1 \le x < 0 \\ 1 - \dfrac{x}{3}, 0 \le x \le 3\end{array}; g\left(x\right) = \left\{−x,−3≤x≤0x,0<x≤1\begin{array}{ll}- x, - 3 \le x \le 0 \\ x, 0 < x \le 1\end{array}\right\right), then range of( f ∘ g ( x ) )$ is

Options

  1. A(0,1]( 0, 1 ]
  2. B[0,3)[ 0, 3 )
  3. C[0,1][ 0, 1 ]
  4. D[0,1)[ 0, 1 )

Correct answer

C. [0,1][ 0, 1 ]

Step-by-step solution

Given: 

f\left(x\right) = \left\{2+2x,x∈[−1,0)1−x3,x∈[0,3]\begin{array}{ll}2 + 2x, x \in [ - 1, 0 ) \\ 1 - \dfrac{x}{3}, x \in \left[0, 3\right]\end{array}\right) and g\left(x\right) = \left\{x,x∈(0,1]−x,x∈[−3,0]\begin{array}{ll}x, x \in ( 0, 1 ] \\ - x, x \in \left[- 3, 0\right]\end{array}\right)</p><p>⇒ f\left(g\left(x\right)\right) = \left\{2+2g(x),g(x)∈[−1,0)1−g(x)3,g(x)∈[0,3]\begin{array}{ll}2 + 2g\left(x\right), g\left(x\right) \in [ - 1, 0 ) \\ 1 - \dfrac{g\left(x\right)}{3}, g\left(x\right) \in \left[0, 3\right]\end{array}\right)

⇒ f\left(g\left(x\right)\right) = \left\{2+2∣x∣,∣x∣∈[−1,0)⇒x∈ϕ1−∣x∣3,∣x∣∈[0,3]\begin{array}{ll}2 + 2\left|x\right|, \left|x\right| \in [ - 1, 0 ) ⇒ x \in ϕ \\ 1 - \dfrac{\left|x\right|}{3}, \left|x\right| \in \left[0, 3\right]\end{array}\right)</p><p>\left\{\text{as}x \in \left[- 3, 3\right]\text{for}\left|x\right| \le 3\text{but}x \in \left[- 3, 1\right]\text{in}g\left(x\right)\right\}</p><p></p><p>⇒ f\left(g\left(x\right)\right) = 1 - \dfrac{\left|x\right|}{3}, x \in \left[- 3, 1\right]</p><p>Now,maximumvalueof</p><p>Now, maximum value off\left(g\left(x\right)\right) = 1 - \dfrac{\left|x\right|}{3} = 1 - \dfrac{0}{3} = 1</p><p>Andminimumvalueisgivenby</p><p>And minimum value is given byf\left(g\left(x\right)\right) = 1 - \dfrac{3}{3} = 1 - 1 = 0</p><p>Hence,therangeofthefunction willbe [0,1]</p><p>Hence, the range of the function will be \left[0, 1\right]

Practice Functions on Quantrex Academy →

More from Functions

Let ℕ denote the set of all positive integers. Consider the sets A = \ 1, 2, 3, 4, 5\ and… JEE Advanced 2026Let f:(1,∞)→ℝ be a function defined as f(x) = (x-1)/(x+1) . Let f^ i+1 (x) = f(f^i(x))… JEE Main 2026Let f be a polynomial function such that _2(f(x)) = ( _2(2+(2)/(3)+(2)/(9)+…∞))·… JEE Main 2026Let f: ℝ arrow ℝ be defined as f(x) = (2x^2 - 3x + 2)/(3x^2 + x + 3) . Then f is : JEE Main 2026Let e be the base of natural logarithm and let f: \ 1, 2, 3, 4\ arrow \ 1, e, e^2, e^3\… JEE Main 2026Let f: R arrow R be a function such that f(x) + 3f((π)/(2) - x) = x , x ∈ R . Let the… JEE Main 2026The sum of all the integral values of p such that the equation 3 ^2 x + 12 x - 3 = p , x… JEE Main 2026Let A = \ 1, 2, 3, 4, 5, 6\ . The number of one-one functions f: A arrow A such that f(1)… JEE Main 2026For the function f:[1,∞) arrow [1,∞) defined by f(x)=(x-1)^4+1 , among the two… JEE Main 2026Let for some α ∈ ℝ , f:ℝarrowℝ be a function satisfying f(x+y)=f(x)+2y^2+y+α xy for all… JEE Main 2026Let [·] denote the greatest integer function. If the domain of the function f(x) = ^ -1… JEE Main 2026The number of functions f: \ 1, 2, 3, 4\ arrow \ a, b, c\ , which are not onto, is: JEE Main 2026If the domain of the function f(x) = _ (0.6) (|(2x-5)/(x^2-4)|) is (-∞, a] \ b\ [c, d)… JEE Main 2026Given below are two statements: Statement I: The function f: R arrow R defined by… JEE Main 2026The sum of all the elements in the range of f(x)=Sgn( x)+Sgn( x)+Sgn( x)+Sgn( x) , x ≠ n… JEE Main 2026If g(x)=3 x^ 2 +2 x-3, f(0)=-3 and 4 g(f(x))=3 x^ 2 -32 x+72 , then f(g(2)) is equal to: JEE Main 2026 Full Functions list Functions JEE Maths PYQsJEE Mathematics PYQs All JEE Main PYQs