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Let f:RrarrR be defined by : f(x)={(2x...

Let `f:RrarrR` be defined by :
`f(x)={(2x,,xgt3),(x^(2),,1ltxlt3),(3x,,xle1):}`
Then, `f(-1)+f(2)+f(4)` is :

A

9

B

14

C

5

D

None of these

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The correct Answer is:
To solve the problem, we need to evaluate the expression \( f(-1) + f(2) + f(4) \) using the piecewise function defined as: \[ f(x) = \begin{cases} 2x & \text{if } x > 3 \\ x^2 & \text{if } 1 < x < 3 \\ 3x & \text{if } x \leq 1 \end{cases} \] ### Step 1: Calculate \( f(-1) \) Since \(-1 \leq 1\), we use the third case of the piecewise function: \[ f(-1) = 3(-1) = -3 \] ### Step 2: Calculate \( f(2) \) Since \(2\) is between \(1\) and \(3\), we use the second case of the piecewise function: \[ f(2) = 2^2 = 4 \] ### Step 3: Calculate \( f(4) \) Since \(4 > 3\), we use the first case of the piecewise function: \[ f(4) = 2(4) = 8 \] ### Step 4: Combine the results Now we can combine the results from the previous steps: \[ f(-1) + f(2) + f(4) = -3 + 4 + 8 \] Calculating this gives: \[ -3 + 4 = 1 \] \[ 1 + 8 = 9 \] Thus, the final answer is: \[ f(-1) + f(2) + f(4) = 9 \] ### Final Answer: \[ \boxed{9} \]
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