The function \( f \) is defined by \( f(x)=x^{2}+4 \sin (2 x) \). Find all values of \( x \) that satisfy the conclusion of the Mean Value Theorem on the interval \( [0,3] \). You may use a calculator and round to the nearest thousandth.
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To apply the Mean Value Theorem (MVT), we first need to check that the function \( f(x) = x^2 + 4 \sin(2x) \) is continuous and differentiable on the interval \([0, 3]\). Since \( f \) is a combination of a polynomial and a sine function, it is both continuous and differentiable on this interval. Next, we find the average rate of change of \( f \) on \([0, 3]\): \[ f(0) = 0^2 + 4 \sin(0) = 0 \] \[ f(3) = 3^2 + 4 \sin(6) \approx 9 + 4(-0.279) \approx 9 - 1.116 \approx 7.884 \] The average rate of change over \([0, 3]\): \[ \frac{f(3) - f(0)}{3 - 0} = \frac{7.884 - 0}{3} \approx 2.628 \] Now by the Mean Value Theorem, there exists at least one \( c \) in \((0, 3)\) such that: \[ f'(c) = \frac{f(3) - f(0)}{3 - 0} \approx 2.628 \] We now find the derivative \( f'(x) \): \[ f'(x) = 2x + 4 \cdot 2 \cos(2x) = 2x + 8 \cos(2x) \] Next, we set the derivative equal to the average rate of change calculated earlier: \[ 2c + 8 \cos(2c) = 2.628 \] To find \( c \), we can use numerical methods or a calculator. Rearranging gives: \[ 8 \cos(2c) = 2.628 - 2c \] \[ \cos(2c) = \frac{2.628 - 2c}{8} \] You would then use a numerical approach (like the Newton-Raphson method or simply graphing) to find the intersection points of these equations. Performing numerical calculations, we find: 1. For \( c \approx 0.733 \) 2. For \( c \approx 2.243 \) Thus, the values of \( x \) that satisfy the conclusion of the Mean Value Theorem on the interval \( [0, 3] \) are approximately \( c \approx 0.733 \) and \( c \approx 2.243 \).