yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Worked example: range of solution curve from slope field | AP Calculus AB | Khan Academy


2m read
·Nov 11, 2024

If the initial condition is (0, 6), what is the range of the solution curve ( Y = F(x) ) for ( x \geq 0 )?

So, we have a slope field here for a differential equation, and we're saying, okay, if we have a solution where the initial condition is (0, 6), so (0, 6) is part of that solution.

Let's see (0, 6). So this is part of the solution, and we want to know the range of the solution curve. You can eyeball a little bit by looking at the slope field.

So, as ( x ), remember ( x ) is going to be greater than or equal to zero, so it's going to include this point right over here. As ( x ) increases, you can tell from the slope, okay, ( y ) is going to decrease, but it's going to keep decreasing at a slower and slower rate.

It looks like it's asymptoting towards the line ( y = 4 ). So, it's going to get really, as ( x ) gets larger and larger, it's going to get infinitely close to ( y = 4 ) but it's not quite going to get there.

So the range, the ( y ) values that this is going to take on, ( y ) is going to be greater than 4. It's not ever going to be equal to 4. So I'll do, it's going to be greater than 4. That's going to be the bottom end of my range, and at the top end of my range, I will be equal to 6.

Six is the largest value that I am going to take on. Another way I could have written this is ( 4 < y \leq 6 ). Either way, this is a way of describing the range, the ( y ) values that the solution will take on for ( x ) being greater than or equal to zero.

If they said for all ( x )'s, well then you might have been able to go back this way and keep going, but they're saying the range of the solution curve for ( x ) is greater than or equal to zero.

So we won't consider those values of ( x ) less than zero. So there you go, the curve would look something like that, and you can see the highest value it takes on is six, and it actually does take on that value because we're including ( x ) equaling zero, and then it keeps going down, approaching 4, getting very, very close to 4 but never quite equaling 4.

More Articles

View All
Under the Dark Skies | National Geographic
More than 130 years ago, before the advent of streetlights, we had the opportunity from the millennia before that to experience a starry night sky. It invited us inspiration and awe. [Music] When you are out under the night sky in the dark, next to your f…
Multiplying and dividing by powers of 10
In another video, we introduce ourselves to the idea of powers of 10. We saw that if I were to just say 10 to the first power, that means that we’re just really just going to take 1. If we have 10 to the second power, that means that we’re going to take …
Constructing t interval for difference of means | AP Statistics | Khan Academy
Let’s say that we have two populations. So that’s the first population, and this is the second population right over here. We are going to think about the means of these populations. So let’s say this first population is the population of golden retrieve…
Remove the Dams to Save the Salmon? | Short Film Showcase
[Music] [Music] If you think about the way a river works in a landscape, it essentially functions as the circulatory system. It drains the waste products off of the land, and that sediment is the stuff that basically structures habitat in rivers. Then, on…
Electronic transitions and energy | AP Chemistry | Khan Academy
In this video we’re going to be talking about exciting electrons. We can interpret that both ways: that electrons can be exciting and that we’re going to excite them into higher energy levels, or we’re going to think about what happens when they get unexc…
Introduction to limits at infinity | Limits and continuity | AP Calculus AB | Khan Academy
We now have a lot of experience taking limits of a function. So if I’m taking the limit of f of x, we’re going to think about what does f of x approach as x approaches some value a. This would be equal to some limit. Now, everything we’ve done up till no…