Monday, October 30, 2017

Calculus: Early Transcendentals, Chapter 4, 4.1, Section 4.1, Problem 54

Given: f(x)=x/(x^2-x+1), [0,3].
Find the critical values by setting the first derivative equal to zero and solving for the x values. Find the derivative using the quotient rule.
f'(x)=[(x^2-x+1)(1)-x(2x-1)]/(x^2-x+1)^2=0
x^2-x+1-2x^2+x=0
-x^2+1=0
x^2=1
x=+-sqrt(1)
x=+-1
The critical values are x=1 and x=-1. Substitute the critical values and the endpoints of the interval [0, 3] in to the original f(x) function. Do NOT substitute in the x=-1 because it is not in the given interval [0, 3].
f(0)=0
f(1)=1
f(3)=3/7
Evaluate the f(x) values to determine the absolute maximum and absolute minimum.
The absolute maximum occurs at the coordinate (1, 1).
The absolute minimum occurs at the coordinate (0, 0).

No comments:

Post a Comment