Boston Bay problemmmsss

Okay so I was all ready to do this scribe post, and then I discovered, I left all my notes at school :[ SO basically all my diagrams are not here with me (atm) and I have to solve alot of the more finicky bits of the problems myself. Yay me! :[

Anyways enough griping, what we did today. To start, we had another little quiz. I'm not really quite fond of these things, although I suppose they're good tools for both Mr.k's and our own assessment of where each individual student is/how well they're doing in the course. As usual we had four questions, and this happened to be one of the no calculator varieties.

So onward with the first question.



So in this question, your given the graph of f(x) and asked to find some information (specifically, which of the 5 points f'(x) < 0 and f''(x)> 0. This for the most part is testing to see if you know what the first and second derivative tell you about the parent function (namely that the first derivative tells you weather the parent function is increasing or decreasing, and the second tells concavity.) Knowing this we find that solving the problem is a simple matter of looking at the concavity around the point, and if at that point on the parent function, it is increasing or decreasing.

Second question



This question 100% wont be on the exam

Why?

Because it's way to simple to be on the exam.

quote endquote of the conversation involving this slide. Pretty much, you just do the red in the picture, take the value of f(x) at 4, subtract is from the value of f(x) at 1, then put that over 4 - 1, then voila. answer. (in this case 4/3)

Neeexxxttttt



This question was also somewhat easy. If you read through the question properly you'll find it's just a direct application of the chain rule. Simply follow the values on the chart, plug em in, and away you go.

FINAL LAP!

dundun dundundun dundeedee!



SO, this one turned out to be a related rates sort of question. The first step here was to write the formula for the volume of a sphere, then differentiate that. Then, you simply begin plugging in some values (namely, a value smaller then 1 and one bigger then one) What you find is that with values of r smaller then 1, the sphere decreases in size, and that with values of larger then 1, the sphere increases in size. Turns out, this is one of the answers. yippee :]

Okay so this is where it gets kinda foggy, so please bear with me guys D:



So this question here, is basically a continuation of the stuff we were doing yesterday, with the funky density questions and the latter rho (whoa Iknorite?). Benchmen showed us the light with this one, so props to him for that goodness.

So in part a.) we need to write a function which will give us the number of cars. We know that the function given describes the traffic in terms of cars/km. To find cars we need to multiply this my Delta km (change in km.) Now as bench said we're actually trying to get really small changes to Delta km ends up ad just dx. (As Shown on the slide)

After all that we put it back together, and find that to find the number of cars, you just do this. (its kinda hard to explain in words so I just cropped it xD)



The next bit of the question (aka. part B.) goes something like this.



Quite simply, all you do is evaluate over the interval 0 to 30 (since you have 30km of road your working with.)

Alrighty guys, its not time for the post titled, BOSTON BAY PROBLEMMMM

dum dun dundundundun.



Now, instead of tackling this whole thing at once, lets start with just part a (or what we started of it anyways before the class ended D:)



So, from what I can tell by looking at the blog, we got as far as setting up the units, (aka, out delta whatever, that becomes the dx.) I'm pretty sure it was around this time the bell rang, and we got our homework and things.

Okay everyone hopefully that wasn't a nightmare to follow, if it was, I apoligize, thats what I get for forgetting my books -_-;

So ja, the next scribe is Paul because I havent picked him in awhile lol.

Ciaooooo

edit: Btw, homework is 8.5 6-10 and the rest of the boston bay problem :]

edit edit: Soo I couldn't leave without some goodness haha