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Find the absolute maximum and minimum values of each of the following in the given intervals :
`f(x)=x^(3)-(5)/(2)x^(2)-2x+1, 0 le x le3.`

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To find the absolute maximum and minimum values of the function \( f(x) = x^3 - \frac{5}{2}x^2 - 2x + 1 \) in the interval \( [0, 3] \), we will follow these steps: ### Step 1: Find the derivative of the function We start by differentiating the function \( f(x) \). \[ f'(x) = \frac{d}{dx}(x^3) - \frac{d}{dx}\left(\frac{5}{2}x^2\right) - \frac{d}{dx}(2x) + \frac{d}{dx}(1) \] Calculating the derivatives, we get: \[ f'(x) = 3x^2 - 5x - 2 \] ### Step 2: Find critical points To find the critical points, we set the derivative equal to zero: \[ 3x^2 - 5x - 2 = 0 \] Now we can solve this quadratic equation using the factorization method or the quadratic formula. Here, we will factor it: \[ 3x^2 - 6x + x - 2 = 0 \] Grouping the terms: \[ 3x(x - 2) + 1(x - 2) = 0 \] Factoring out \( (x - 2) \): \[ (3x + 1)(x - 2) = 0 \] Setting each factor to zero gives us: \[ 3x + 1 = 0 \quad \Rightarrow \quad x = -\frac{1}{3} \quad \text{(not in the interval [0, 3])} \] \[ x - 2 = 0 \quad \Rightarrow \quad x = 2 \quad \text{(in the interval [0, 3])} \] ### Step 3: Evaluate the function at critical points and endpoints We need to evaluate \( f(x) \) at the critical point \( x = 2 \) and the endpoints \( x = 0 \) and \( x = 3 \). 1. **At \( x = 0 \)**: \[ f(0) = 0^3 - \frac{5}{2}(0^2) - 2(0) + 1 = 1 \] 2. **At \( x = 2 \)**: \[ f(2) = 2^3 - \frac{5}{2}(2^2) - 2(2) + 1 \] \[ = 8 - \frac{5}{2}(4) - 4 + 1 \] \[ = 8 - 10 - 4 + 1 = -5 \] 3. **At \( x = 3 \)**: \[ f(3) = 3^3 - \frac{5}{2}(3^2) - 2(3) + 1 \] \[ = 27 - \frac{5}{2}(9) - 6 + 1 \] \[ = 27 - \frac{45}{2} - 6 + 1 \] \[ = 27 - 22.5 - 6 + 1 = -0.5 \] ### Step 4: Compare the values Now we compare the function values at the endpoints and the critical point: - \( f(0) = 1 \) - \( f(2) = -5 \) - \( f(3) = -0.5 \) ### Conclusion The absolute maximum value of \( f(x) \) in the interval \( [0, 3] \) is \( 1 \) at \( x = 0 \), and the absolute minimum value is \( -5 \) at \( x = 2 \). ### Final Answer - Absolute Maximum: \( 1 \) at \( x = 0 \) - Absolute Minimum: \( -5 \) at \( x = 2 \)
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