OFFICIAL AP Calculus BC 2012 Test Thread

Test Preparation AP Mathematics & Computer Science
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<p>I made some dumb mistakes on that test… I’m so ashamed and worried at the same time…
Most likely you’re going to feel like you got a 2 or 3 but end up with a 4 … and feeling you got a 4, end up with a 5.</p>

<p>Especially FRQs, you don’t know the score distribution of each FRQ question. You could have put the work down, but some math error so a couple points gained and a few lost.</p>

<p>You basically won’t know what you got till July unless you know you did horrible or you did extremely well.</p>

<p>The curve however probably won’t change as much. It will depend on how students did throughout the nation. I know for a fact a majority of us are saying it was easy cause you guys are freaking nerds!! and your only .01% of the students who took it -.-</p>

<p>the curve probably won’t change much because half the people in my school who took it said it was ridiculously hard</p>

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<p>O wow… thats bad… half them are chinese lol</p>

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<p>If you do a bunch of FRQs, you get used to the score distribution. Like separation of variables is always worth 5 points.</p>

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<p>what is separation of variables? you mean finding the equation/solution to a differential equation?</p>

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<p>Separation of variables involves setting up the differential equation in the form of y dy = x dx and then integrating both sides.</p>

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<p>So the test was a lot easier than my actual ap calculus class. I looked at the questions and went through them fairly quickly, knowing that I actually did well. Compared to my calculus class, this was nothing. Revere High prepared us very well; over 20 pages of practice problems PER lesson and never end practice on FRQ and multiple choice. I am confident that I passed the test with no sweat.</p>

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<p>Did anyone else’s free response not include the bird problem? I looked on the ap site and the frq they have up is not the one I got (or about half of my class…)</p>

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<p>@dance698548 You must have had the other form that they give to a small percentage of testers</p>

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<p>@MoldyBrick. Thanks! Do you know if we get the same curve as everyone else, or just the people that took that specific test?</p>

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<p>@dance698548 I assume they would base the curve off of the specific test you took. They want to make sure that your score is what they would give to a person that took the other form so I presume they have to deal with some variation in testing difficulty</p>

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<p>FRQs have been released! Is there anyway of finding the answers? Only the questions have been posted.</p>

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<p>Here’s a link to it: <a href=“Supporting Students from Day One to Exam Day – AP Central | College Board”>Supporting Students from Day One to Exam Day – AP Central | College Board;

<p>We can start a list of answers; the actual rubric wont be posted for another couple of months. I’ll add to it when I get a chance</p>

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<p>1.)</p>

<p>(a) 1.017 degrees Fahrenheit per minute. At time t = 12, the temperature of the water in the tub is increasing at a rate of approximately 1.017 degrees Fahrenheit per minute. </p>

<p>(b) W(20) - W(0) = 16 degrees Fahrenheit. After 20 minutes, the total change in temperature was 16 degrees Fahrenheit.</p>

<p>(c) 60.79 degrees Fahrenheit. This is an underestimate of the average temperature of the water because W(t) is strictly increasing.</p>

<p>(d) 71 + int(W’(t),x,20,25) = 73.043 degrees Fahrenheit.</p>

<p>I’m pretty sure those are the answers for #1.</p>

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<p>yeah i got those too. this problem was like the tea and biscuits one from the ab exam last year</p>

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<p>also for 6 B) with the la grange remainder crap, what did you all get. i got 1/3824, but i’m 99.5% sure i got that wrong because my teacher said it was hopeless for me to study it so i didnt</p>

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<p>5.)</p>

<p>(a) The bird is gaining weight faster when it weighs 40 grams because dB/dt is larger when B = 40</p>

<p>(b) d^2B/dt^2 = (-1/25)(100-B) This shows that B must be concave down on the whole interval shown on the graph, but the graph is concave up for the first half.</p>

<p>(c) B(t) = 100 - 80e^((-1/5)kt) if I remember correctly</p>

<p>and @oohabean I got 1/224</p>

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<p>Is there any way of finding the answers to the FRQs? The questions for 2012 have been posted but not the solutions.</p>

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<p>you can either wait until august when they post it or trust the answers people post here and on other websites.most of them are good, though i disagree with a few of the ap chem answers people got…</p>

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<p>dammit moldy brick lol. one of my classmates got that and i think she was the only one who got remainder on the test right. anyway congrats on that one, hopefully i did the rest of the problem right</p>

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<p>Might have made some mistakes since I rushed doing it over again. Just correct as needed.</p>

<p>1-
a) 1.017 degrees F/minute, the temperature of the water is changing at a rate of approximately 1.017 degrees per minute at time 12.
b) 16 degrees F- the water rose 16 degrees from 0 to 20 minutes
c) 60.79 degrees F, understated, the largest temperature is excluded in the left hand approximation and the temperature is strictly increasing over time.
d) 73.043 degrees F</p>

<p>2-
a) It’s going to the right because dx/dt is positive, slope= 3.055
b) 1.253
c) speed= .575, acceleration vector= <-.0411, .989>
d) .651</p>

<p>3-
a) -1/4, (pi-3)/2
b) 2, 1
c) at -1 and 1. -1 is a maximum because the sign chart shows it going from + to -, but 1 is nothing.
d) at -2, 0, 1. These are the points where f’ changes sign.</p>

<p>4-
a) 18.2
b) 19.6
c) 19
d) 19.8</p>

<p>5-
a) It gains weight faster at 40 because plugging in 40 to the rate given compared to 70 results in a greater rate.
b) db/dt= -1/25[100-B]. Using sign chart, 0= -, 200= +, so 100 is a point of inflection. The graph doesn’t show it.
c) y= 100-80e^(-1/5t)</p>

<p>6-
a) -1<=x<=1
b) 1/224 is the first neglected term and must be greater than the error according to ASRT. 1/224 is less than 1/200 so the approximation error is less than 1/200.
c) 1/3-3x^2/5+5x^4/7…[(-1)^n(2n+1)x^2n]/[2n+3]</p>