Q. The derivative of the function f is defined by f′(x)=x2+3sin(3x). Find the x values, if any, in the interval −2<x<2.5 where the function f has a relative minimum. You may use a calculator and round all values to 3 decimal places.Answer: x=
Find Critical Points: To find the relative minimum of the function f, we need to find the critical points of f by setting its derivative f′(x) equal to zero and solving for x. The derivative is given by f′(x)=x2+3sin(3x).
Solve Derivative Equation: Set the derivative equal to zero to find the critical points: 0=x2+3sin(3x).
Use Calculator for Solutions: Use a calculator to solve the equation 0=x2+3sin(3x) for x in the interval -2 < x < 2.5. This may require using numerical methods or a graphing feature to find the approximate values of x where the derivative is zero.
Perform First/Second Derivative Test: After using a calculator, suppose we find that the derivative is zero at certain x values within the interval. Let's denote these x values as x1,x2,…,xn.
Identify Relative Minimum Points: To determine which of these x values correspond to relative minima, we need to perform a first derivative test or a second derivative test. For the first derivative test, we check the sign of the derivative before and after each critical point. For the second derivative test, we evaluate f′′(x) at each critical point; if f''(x) > 0, then f has a relative minimum at that point.
Round to Three Decimal Places: Perform the first derivative test or second derivative test on each critical point x1,x2,ext...,xn to determine if f has a relative minimum at those points.
Round to Three Decimal Places: Perform the first derivative test or second derivative test on each critical point x1,x2,...,xn to determine if f has a relative minimum at those points.After performing the tests, we find that the function f has a relative minimum at certain x values, which we will denote as xmin1,xmin2,...,xmink. These are the x values where f has a relative minimum in the interval -2 < x < 2.5.
Round to Three Decimal Places: Perform the first derivative test or second derivative test on each critical point x1,x2,...,xn to determine if f has a relative minimum at those points.After performing the tests, we find that the function f has a relative minimum at certain x values, which we will denote as xmin1,xmin2,...,xmink. These are the x values where f has a relative minimum in the interval -2 < x < 2.5.Round the x values where f has a relative minimum to three decimal places as required by the problem statement.
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