Increasing And Decreasing Functions Part 1
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This lesson discusses using the derivative to determine where a function is increasing or decreasing. this is the first part of a two part lesson. this les. At x = −1 the function is decreasing, it continues to decrease until about 1.2; it then increases from there, past x = 2; without exact analysis we cannot pinpoint where the curve turns from decreasing to increasing, so let us just say: within the interval [−1,2]: the curve decreases in the interval [−1, approx 1.2].
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No, the question is whether the function f(x) is positive or negative for this part of the video. that means, according to the vertical axis, or "y" axis, is the value of f(a) positive is f(x) positive at the point a?. Figure 3.3.1 3.3. 1: a graph of a function f f used to illustrate the concepts of increasing and decreasing. even though we have not defined these terms mathematically, one likely answered that f f is increasing when x > 1 x > 1 and decreasing when x < 1 x < 1. we formally define these terms here. Definition of an increasing and decreasing function. let y = f (x) be a differentiable function on an interval (a, b).if for any two points x 1, x 2 ∈ (a, b) such that x 1 < x 2, there holds the inequality f(x 1) ≤ f(x 2), the function is called increasing (or non decreasing) in this interval. Example 1: determine the interval (s) on which f (x) = xe x is increasing using the rules of increasing and decreasing functions. solution: to determine the interval where f (x) is increasing, let us find the derivative of f (x). hence, we have f' (x) > 0 for x < 1.
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Definition of an increasing and decreasing function. let y = f (x) be a differentiable function on an interval (a, b).if for any two points x 1, x 2 ∈ (a, b) such that x 1 < x 2, there holds the inequality f(x 1) ≤ f(x 2), the function is called increasing (or non decreasing) in this interval. Example 1: determine the interval (s) on which f (x) = xe x is increasing using the rules of increasing and decreasing functions. solution: to determine the interval where f (x) is increasing, let us find the derivative of f (x). hence, we have f' (x) > 0 for x < 1. 1.7: 1.7 increasing and decreasing. it is important to be able to distinguish between when functions are increasing and when they are decreasing. in business this could mean the difference between making money and losing money. in physics it could mean the difference between speeding up and slowing down. The first graph shows an increasing function as the graph goes upwards as we move from left to right along the x axis. the second graph shows a decreasing function as the graph moves downwards as we move from left to right along the x axis. important notes on increasing and decreasing intervals.
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1.7: 1.7 increasing and decreasing. it is important to be able to distinguish between when functions are increasing and when they are decreasing. in business this could mean the difference between making money and losing money. in physics it could mean the difference between speeding up and slowing down. The first graph shows an increasing function as the graph goes upwards as we move from left to right along the x axis. the second graph shows a decreasing function as the graph moves downwards as we move from left to right along the x axis. important notes on increasing and decreasing intervals.
![](https://i0.wp.com/sicepat.com/images/image-not-found.png)
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