<p>Will we be asked to sketch curves on the current AP Calc exam? </p>
<p>I saw a curve sketching question on the 1998 FRQs and curve sketching is also covered by my Princeton Review AP Calc book … the 2010 edition too :eek:.</p>
<p>Hey, does anyone have any good ap review book recommendations? I’ve been looking at Barrons and PR so far, but I’m leaning a little for towards Barrons just cuz it has 4 practice tests.</p>
<p>^I have a copy of PR and Barron’s sitting in front of me. I recommend PR over Barron’s. </p>
<p>PR explains the material better than Barron’s. Barron’s just presents a couple of formulas and some example problems. PR guides you through the steps. </p>
<p>PR is simple. Barron’s is erudite. As far as practice tests go, I have never touched a PR or Barron’s practice test. The FRQs on CB’s website are all I need. I don’t think the practice tests in the books are worth it when you have all the released material.</p>
<p>Hey, guys! Does anyone know the Application of integration, particularly about Volume? It’s my shortcoming, can somebody explain it for me, please?</p>
<p>Also, can somebody tell me how many questions can I missed in order to keep up a 5 on the AB exam? Both from the MC section and FRQ section. Thanks!!</p>
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<p>Volume FRQs are relatively simple. </p>
<p>The volume is pi * the integral of the upper minus the bottom curve for vertical slices or pi * the integral of the right minus the left curve for horizontal slices. Adjust the bounds of the integral as needed; x-bounds for vertical slices; y-bounds for horizontal slices.</p>
<p>OwenHe, PatrickJMT has a a lot of volume integration videos on YouTube.</p>
<p>Here’s one: [Volumes</a> of Revolution - Disk/Washers Example 1 - YouTube](<a href=“Volumes of Revolution - Disk/Washers Example 1 - YouTube”>Volumes of Revolution - Disk/Washers Example 1 - YouTube)</p>
<p>He does a really good job of explaining.</p>
<p>I’m taking AP Calc next year, and this appears to be a good thread for this question: What calculator is best for the exam? Will any new calculator be coming out between now and August that I should wait for?</p>
<p>Just get a ti-83 or ti-84. those will work perfectly fine for AB Calc</p>
<p>I’m going to get a TI-Nspire CX CAS and I will be laughing at you intellectual inferiority when I am doing integrals in terms of variables in my calculator. :p</p>
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<p>lol just wait till they throw one at you where you cant solve for x and you have to use complete the square; there are myriad ways CB can make volume problems difficult.</p>
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<p>There are also a myriad of ways CB can make limits hard. They could make x approach 3 and give you a 7th degree polynomail. There are also a myriad of ways CB could make derivatives hard. They could give you only derivatives with bases a and polynomials for exponents. Needless to say, there are ways to make problems hard :). </p>
<p>After going through most of the volume FRQ problems, I can’t say that I have seen one that requires completing the □.</p>
<p>Yeah, for some reason I tend to do well on the volume methods (disk, washer, and shell), but I don’t feel as comfortable with them as I do with everything else. It’s weird. =/</p>
<p>^There are only two steps to volume problems:</p>
<p>1) Horizontal or vertical rectangles?</p>
<p>Horizontal: make everything y = something. Use y bounds, a dy term, and make the equations in terms of x, so x equals some quantity of y. Right minus left curve. </p>
<p>Vertical: make everything x = something. X bounds, dx term, and y = equation. Top minus bottom curve. </p>
<p>For washers just remember that the radius is always the distance from the curve to the axis of revolution. You can’t go wrong.</p>
<p>Yeah, I dunno, I did great on the quiz on this stuff, I just don’t feel comfortable. Just a question:
Say you rotate f(x) = x^2 around y = 4. Why would you choose the radius to be (4-x^2)^2 as opposed to 16 - x^4? My main problem is differentiating between when to use those two situations.</p>
<p>Hey guys, so i just had a mock AP test and I scored a 4 (barely made it) and I wanted to review myself for about a month before the test. I was looking at some books like Princeton’s and Barron’s and the reviews are confusing. Some say the books are great and others say there the worst possible books you could get. To the people who bought these books, which one is better to score a 5?</p>
<p>@Fast Neutrino: To clarify the question a bit, let’s take a region bound by y = 4, y = x^2, and the y-axis (x = 0). When you’re rotating around the line y = 4, the axis of revolution is one of the boundaries of the region. Accordingly, you only need one radius, and that radius will be the distance between the curves y = 4 and y = x^2. Find that distance by subtracting, and your integral would be Integral (from x = 0 to x = 2) of (4 - x^2)^2 dx.</p>
<p>Contrast that with the situation where you’re rotating the same region about the x-axis (y = 0). Note now that the axis of revolution is not one of the boundary lines of the region. So you’ll need two separate radii: one for the outer boundary of your “washer” and one for the inner boundary. The outer radius is the distance from y = 4 to the axis of revolution (which is 4), and the inner radius is the distance from y = x^2 to the axis of revolution (which is x^2). So your integral here is Integral (from x = 0 to x = 2) of [(4)^2 - (x^2)^2] dx.</p>
<p>Okay, that actually makes a lot of sense. Thanks!</p>
<p>I need help on a problem:
A marble rolls down a ramp that is 2 feet from the door, and comes to a stop after 5 seconds. Its velocity during this time-frame is modeled by: v(t)=t^2-0.2t^3 ft/sec. Find how far the marble travels and how far it is from the door at t=5.</p>
<p>So far I’ve done:
Integral from 0 to 5 of t^2-0.2t^3 dt
= [1/3t^3 - 0.2t^4/4] integral from 0 to 5
= [125/12]-[0]
= 125/12</p>
<p>Am I doing this right?</p>
<p>You got the first part right I think. For the second part of the question take the definite integral and subtract it from 2, so 125/12 ft - 24/12 ft = 101/12 ft</p>