Math Problem Statement
The derivative of the function f is defined by f′(x)=(*x^*2+2)cos(x+5). What is the x-coordinate of the absolute maximum value of the function f on the closed interval [−4,2]? You may use a calculator and round your answer to the nearest thousandth.
Solution
To find the absolute maximum value of the function on the closed interval , we will apply the First Derivative Test and evaluate the function at critical points and at the endpoints.
Steps to solve:
-
Find the critical points: The critical points occur when . We're given . To find critical points, set : Since for any real (because ), the only way this product equals 0 is when:
-
Solve : The cosine function is zero at , for integer . Therefore: Solving for : This gives us a general solution for , but we are only interested in solutions within the interval .
-
Find specific solutions: By substituting different integer values of and solving for , we get the possible critical points within the interval :
- For ,
- For ,
So the critical points are and .
-
Evaluate the function at the critical points and endpoints: Since we do not have an explicit formula for , we can only evaluate the function at the critical points and endpoints using the information from .
The endpoints are and .
-
Determine the absolute maximum: Using the calculator, evaluate the function at the critical points and the endpoints (by analyzing the sign changes of around those points) to find the -coordinate where has an absolute maximum.
After evaluating, the absolute maximum occurs at .
Conclusion:
The -coordinate of the absolute maximum value of the function on the closed interval is approximately .
Would you like further details or clarifications on any of these steps?
Here are some related questions:
- How do we find critical points for a general function?
- What is the First Derivative Test, and how does it work?
- How can we evaluate trigonometric equations like in different intervals?
- What is the significance of closed intervals in optimization problems?
- How does the behavior of the derivative inform us about maximum and minimum points?
Tip: Always check both critical points and endpoints when looking for absolute extrema on a closed interval.
Ask a new question for Free
By Image
Drop file here or Click Here to upload
Math Problem Analysis
Mathematical Concepts
Calculus
Critical Points
Maxima and Minima
Trigonometric Functions
Formulas
f'(x) = (x^2 + 2)cos(x + 5)
cos(x) = 0
Theorems
First Derivative Test
Critical Point Theorem
Suitable Grade Level
College Calculus