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If f(x)=begincases2+2x,& -1le x lt 0\\ 1-fracx3,& 0le xle 3endcases; g(x)=begincases-x,& -3le xle 0\\ x,& 0 lt xle 1endcases , then range of (fog(x)) is

Solution & Explanation

### Related Formula f(g(x)) = f(y) quad textwhere y = g(x) The domain restrictions of f(y) must be cross-checked against the range evaluated for g(x). ### Core Logic First, analyze the range of the inner function g(x): g(x) = -x for -3 le x le 0. The range here is [0, 3]. g(x) = x for 0 lt x le 1. The range here is (0, 1]. Therefore, the complete range of g(x) across its entire domain [-3, 1] is [0, 3]. Note that g(x) ge 0 for all valid x.
Composite Functions
Composite Functions
Now, plug g(x) into f(x): f(g(x)) = begincases2+2g(x),& -1 le g(x) lt 0 quad dots (1) \\ 1-fracg(x)3,& 0 le g(x) le 3 quad dots (2)endcases
Composite Functions
Composite Functions
### Step 1: Evaluate the Branches Check branch (1): -1 le g(x) lt 0. Since we already established the range of g(x) is entirely non-negative (g(x) ge 0), this branch condition is never satisfied. No values of x map here (x in phi). Check branch (2): 0 le g(x) le 3. This perfectly aligns with the entire range of g(x). Hence, this branch is active for all x in [-3, 1]. We evaluate f(g(x)) = 1 - fracg(x)3. Since g(x) spans all values continuously from 0 to 3: When g(x) = 0 Rightarrow f(g(x)) = 1 - 0 = 1. When g(x) = 3 Rightarrow f(g(x)) = 1 - 1 = 0. Since g(x) is continuous and covers [0, 3], 1 - fracg(x)3 covers [0, 1] continuously. ### Step 2: Final Conclusion The range of f(g(x)) is purely evaluated from branch (2), leading to [0, 1]. ### Pattern Recognition When finding the range of f(g(x)), evaluate the global range of g(x) first. Use that resulting interval as the "domain" input for f(x) to trace the final output bounds, eliminating unneeded piecewise branches. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Mathematics: Sets, Relations and Functions

Reference Study Guides

More Sets, Relations and Functions Previous-Year Questions — Page 10

Q29 jee_main_2024_31_jan_morning Equivalence Relations
Let A = \1, 2, 3, 4\ and R = \(1, 2), (2, 3), (1, 4)\ be a relation on A. Let S be the equivalence relation on A such that R subset S and the number of elements in S is n. Then, the minimum value of n is
Numerical Answer. Answer: 16 to 16

Solution

### Core Logic S must be reflexive, symmetric, and transitive, containing (1,2), (2,3), and (1,4). Symmetric property forces (2,1), (3,2), (4,1) in S. Transitive property: (1,2) and (2,3) implies (1,3) in S. Symmetric implies (3,1) in S. (4,1) and (1,2) implies (4,2) in S. Symmetric implies (2,4) in S. (4,1) and (1,3) implies (4,3) in S. Symmetric implies (3,4) in S. ### Step 1: Universal Relation Since 1 is related to 2, 3, 4 and the relation is an equivalence relation (which creates partitions), all elements 1, 2, 3, and 4 must fall into the same single equivalence class. Thus, S must contain all possible ordered pairs in A times A. ### Step 2: Final Count Number of elements in A times A = 4 times 4 = 16. Minimum value of n is 16. ### Pattern Recognition If a relation connects all elements in a set to each other through a chain, its equivalence closure is the universal relation A times A. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 12 Maths: Relations and Functions

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