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If f: R to R be defined by f(x)={(2x:xgt...

If `f: R to R` be defined by `f(x)={(2x:xgt3),(x^(2):1lt x le 3),(3x:x le 1):}`
Then,`f(-1)+f(2)+f(4)` is

A

9

B

14

C

5

D

None of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to evaluate the function \( f(x) \) at three different points: \( f(-1) \), \( f(2) \), and \( f(4) \). The function \( f \) is defined piecewise as follows: - \( f(x) = 2x \) for \( x > 3 \) - \( f(x) = x^2 \) for \( 1 < x \leq 3 \) - \( f(x) = 3x \) for \( x \leq 1 \) Now, let's evaluate each of the required values step by step. ### Step 1: Calculate \( f(-1) \) Since \( -1 \leq 1 \), we use the third piece of the function: \[ f(-1) = 3(-1) = -3 \] ### Step 2: Calculate \( f(2) \) Since \( 2 \) lies between \( 1 \) and \( 3 \) (i.e., \( 1 < 2 \leq 3 \)), we use the second piece of the function: \[ f(2) = 2^2 = 4 \] ### Step 3: Calculate \( f(4) \) Since \( 4 > 3 \), we use the first piece of the function: \[ f(4) = 2(4) = 8 \] ### Step 4: Sum the values Now we sum the results from the previous steps: \[ f(-1) + f(2) + f(4) = -3 + 4 + 8 \] Calculating this gives: \[ -3 + 4 = 1 \] \[ 1 + 8 = 9 \] ### Final Result Thus, the value of \( f(-1) + f(2) + f(4) \) is: \[ \boxed{9} \] ---

To solve the problem, we need to evaluate the function \( f(x) \) at three different points: \( f(-1) \), \( f(2) \), and \( f(4) \). The function \( f \) is defined piecewise as follows: - \( f(x) = 2x \) for \( x > 3 \) - \( f(x) = x^2 \) for \( 1 < x \leq 3 \) - \( f(x) = 3x \) for \( x \leq 1 \) Now, let's evaluate each of the required values step by step. ...
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NCERT EXEMPLAR-RELATIONS AND FUNCTIONS-Relations And Functions
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  3. Let f:N rarr R be the function defined by f(x)=(2x-1)/2 and g:Q rarr Q...

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  4. If f: R to R be defined by f(x)={(2x:xgt3),(x^(2):1lt x le 3),(3x:x le...

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  5. If f:R to R be given by f(x)= tan x, then f^(-1)(1) is

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  6. Let the relation R be defined in N by a R b, if 2a + 3b = 30. Then R =...

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  7. If the relation R be defined on the set A={1,2,3,4,5} by R={(a,b): |a^...

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  8. If the functions f and g are given by f={(1,\ 2),\ (3,\ 5),\ (4,\ 1)} ...

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  9. If f:R to R be defined by f(x) = (x)/(sqrt(1 +x^(2) )), then (fofof)...

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  10. If f(x) = [4-(x-7)^(3)], then f^(-1)(x)= ………… .

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  11. State true or false for the given statement : Let R = { (3, 1), (1,...

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  12. If f:R to R be the function defined by f(x) = sin(3x+2) AA x in R. Th...

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  13. Every relation which is symmetric and transitive is also reflexive.

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  14. An integer m is said to be related to another integer n if m is a m...

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  15. Let A = {0, 1} and the set of all natural numbers.Then the mapping f: ...

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  16. The relation R on the set A = {1, 2, 3} defined as R ={(1, 1), (1, 2),...

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  17. The composition of function is commutative.

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  18. The composition of functtions is associative

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  19. Every function is invertible.

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  20. A binary operation on a set has always the identity element.

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