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March 29, 2024, 03:04:36 am

Author Topic: 3U Maths Question Thread  (Read 1230302 times)  Share 

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Neutron

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Re: 3U Maths Question Thread
« Reply #75 on: March 25, 2016, 11:33:00 pm »
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Hey Neutron!

Tan-1(tanx) will cancel each other out, leaving us simply with y = x. So all you need to do is plot the points (pi, pi) and
(-pi, -pi), and then connect these two points (essentially just the linear graph y=x).

If you really need me to show you the sketch just tell me, but Im sure you are capable of doing it! :)

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Happy Physics Land

Yeah I know that but the answer gave me something very trippy :'( I'll see if I can upload a pic later D:

RuiAce

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Re: 3U Maths Question Thread
« Reply #76 on: March 25, 2016, 11:48:04 pm »
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Yeah I know that but the answer gave me something very trippy :'( I'll see if I can upload a pic later D:












Your hint is to think about both the domains AND ranges of both the tangent function, and it's inverse.
« Last Edit: March 25, 2016, 11:58:15 pm by RuiAce »

Happy Physics Land

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Re: 3U Maths Question Thread
« Reply #77 on: March 26, 2016, 12:01:31 am »
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Your hint is to think about both the domains AND ranges of both the tangent function, and it's inverse.

Yeah I know that but I was assuming a -pi <= x <= pi
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RuiAce

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Re: 3U Maths Question Thread
« Reply #78 on: March 26, 2016, 12:04:55 am »
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Yeah I know that but I was assuming a -pi <= x <= pi

Tangent discontinues at pi/2. Not pi.

Happy Physics Land

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Re: 3U Maths Question Thread
« Reply #79 on: March 26, 2016, 12:42:38 am »
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Tangent discontinues at pi/2. Not pi.

Oh
wait
Yeah
True......
Sorry Neutron bro I failed you!
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amandali

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Re: 3U Maths Question Thread
« Reply #80 on: March 26, 2016, 06:47:02 am »
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How do you do the last part  for the first question ?
please help thanks

RuiAce

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Re: 3U Maths Question Thread
« Reply #81 on: March 26, 2016, 09:08:58 am »
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How do you do the last part  for the first question ?
please help thanks

Mind posting the solutions to the previous parts? They seem to be useful for the answer to d)

Not sure if the perms/combs question was intentionally placed there but that one isn't too bad.







RuiAce

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Re: 3U Maths Question Thread
« Reply #82 on: March 26, 2016, 09:22:58 am »
+1
How do you do the last part  for the first question ?
please help thanks




Except, of course, this is the rigorous approach. I'm not too sure what the question means by to use the calculator.

xus2016

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Re: 3U Maths Question Thread
« Reply #83 on: March 27, 2016, 02:16:09 pm »
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How do you integrate cosec3xcot3x?

Happy Physics Land

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Re: 3U Maths Question Thread
« Reply #84 on: March 27, 2016, 04:30:49 pm »
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How do you integrate cosec3xcot3x?

Hey Xus!

Interesting question! Ok to do this question, we would use 3 unit integration by substitution, I have posted my solution below, if you have any further questions please dont hesitate to ask! :) :)

(Sorry if the image is a bit blurry, still using brick phones hehe :D )



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amandali

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Re: 3U Maths Question Thread
« Reply #85 on: March 27, 2016, 04:55:00 pm »
+1
Mind posting the solutions to the previous parts? They seem to be useful for the answer to d)

Not sure if the perms/combs question was intentionally placed there but that one isn't too bad.









these are the solutions for previous parts

RuiAce

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Re: 3U Maths Question Thread
« Reply #86 on: March 27, 2016, 10:49:35 pm »
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How do you integrate cosec3xcot3x?
Hey Xus!

Interesting question! Ok to do this question, we would use 3 unit integration by substitution, I have posted my solution below, if you have any further questions please dont hesitate to ask! :) :)

(Sorry if the image is a bit blurry, still using brick phones hehe :D )

(Image removed from quote.)

Best Regards
Happy Physics Land



Note that the internationally accepted form of cosecant is csc, which is what LaTeX observes. Interpret as cosec always.

RuiAce

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Re: 3U Maths Question Thread
« Reply #87 on: March 27, 2016, 10:58:14 pm »
+2

these are the solutions for previous parts





mmadeleine

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Re: 3U Maths Question Thread
« Reply #88 on: March 29, 2016, 08:33:59 pm »
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Hi all,
Really struggling with part C of this 3D trig question, I just can't seem to get it out...
Help would be very much appreciated!

Thankyou!!  :)

katherine123

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Re: 3U Maths Question Thread
« Reply #89 on: March 29, 2016, 09:23:55 pm »
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Not sure how to get C