Discussion of 2009 AP BC Calc Free-Responce Answers

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61

<p>well for both of the question in 5 the answer should be the same as what they told you to prove it was less or greater than. You had to explain that because it the second derivative was less than zero, the approximations were either greater or less than</p>

62

<p>For 3d. (the diver’s angle problem), I just did vx=vcos(theta) ((from physics)). I wonder if that’s valid…</p>

63

<p>UGH. Hahahaha. I had no idea how to do 3d. But it seems I got everythingn else right except 2d and 5c, so I’m feeling pretty good. Hopefully I didn’t screw up the multiple choice terribly. Good luck to all you guys!!</p>

64

<p>What happens if you miss a negative sign?</p>

65

<p>Guys, isn’t 2d) just integrate w’(t) from 0 to 2 then divide by 980?</p>

66

<p>^yes (10 char)</p>

67

<p>… are you serious vicious?</p>

68

<p>Here’s my answers:
1.
a) -.1 m/s^2
b) 1.35
c) t=2
d) Caren
2.
a) 980
b) t=1.363
c)
d)21.052
3.
a)
b)
c)
d)
4.
a) 4.25
b)
c)
5.
a) -3
b) 8
c)
d)
6.
a)
b)
c)
d) one point</p>

69

<p>anyone in BCMath chat on AIM?</p>

70

<p>3d was definently t=0 to t=2, and on question 1 I also didnt see the scale of .1 instead of 1 if i did everything right if the scale was 1 will i get any credit?</p>

71

<p>Is there a consolidated answer for the answer to the differential equation for #4c.</p>

72

<p>i also got ioc of 0-2 on 6c</p>

73

<p>Dangit, for the differential equation for 4C, the U sub made the left side negative LN but I just took the negative out because I thought the LN was absolute value… so my answer was right, but negatively. Will I get credit?</p>

74

<p>ok guys lets start a chat. i made one, just long in with user names…[AIM</a> Chat](<a href=“http://chat-beta.aim.com/chats/special-interests/ccapcalcbc-]AIM”>http://chat-beta.aim.com/chats/special-interests/ccapcalcbc-)</p>

75

<p>you dont divide by 980</p>

76

<p>I’m pretty sure the answer for the angle of the diver was 1.519 rad, which is about 87 degrees</p>

<p>I did theta = arc tan ((dy/dt)/(dx/dt)), which was something like arc tan (15.8/0.8). I thought of it as a triangle the diver forms with the surface of the water the instant before the diver hits the water.</p>

77

<p>Answers -> Please add to list
1.
a) -.1 m/s^2
b) 1.35
c) t=2
d) Caren
2.
a) 980
b) t=1.363
c)
d)21.052
3.
a).661
b)12.722 m
c)
d)
4.
a) 4.25
b)
c)
5.
a) -3
b) 8
c)
d)
6.
a)
b)
c)
d) no points?</p>

<p>Here’s parts a and b for number 3:
[Free</a> Math Help.com - Homework Help! • View topic - 2009 AP Calculus BC Test Answers](<a href=“http://freemathhelp.com/forum/viewtopic.php?f=3&t=34183]Free”>http://freemathhelp.com/forum/viewtopic.php?f=3&t=34183)</p>

78

<p>Answers -> Please add to list
1.
a) -.1 m/s^2
b) 1.35
c) t=2
d) Caren
2.
a) 980
b) t=1.363
c)387.5 (its was 38X.5)
d)21.052
3.
a).661
b)12.722 m
c)
d)
4.
a) 4.25
b)
c)
5.
a) -3
b) 8
c)
d)
6.
a)
b)
c)
d) no points?</p>

79

<p>Answers -> Please add to list
1.
a) -.1 m/s^2
b) 1.35
c) t=2
d) Caren
2.
a) 980
b) t=1.363
c)387.5 (its was 38X.5)
d)21.052
3.
a)12.722 m
b)1.936 seconds
c)
d)
4.
a) 4.25
b)
c)6-4e^(-1/3)(e^(-x^3/3) (if i remember correctly)
5.
a) -3
b) 8
c)18
d)
6.
a)(x-1)^2n/x!
b)(x-1)^2n/(x+1)!
c)-INFINITY to +INFINITY (aka convergent everywhere)
d) no points</p>

80

<p>^ Are you sure that’s how you do 3 A anb B? Seems wrong</p>