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March 29, 2024, 08:46:39 am

Author Topic: 3U Maths Question Thread  (Read 1230394 times)  Share 

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RuiAce

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Re: 3U Maths Question Thread
« Reply #270 on: June 29, 2016, 04:39:03 pm »
+2
If yes

140498

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Re: 3U Maths Question Thread
« Reply #271 on: June 29, 2016, 05:07:13 pm »
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My computer is stuffing up it did not copy properly

all information is correct except:
radius = 20
depth = 30

Really sorry  :(

RuiAce

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Re: 3U Maths Question Thread
« Reply #272 on: June 29, 2016, 05:13:28 pm »
+1
Just repeat the working out then for 30/20=h/r

So r=2h/3

140498

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Re: 3U Maths Question Thread
« Reply #273 on: June 29, 2016, 05:29:35 pm »
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ok thanks :)

140498

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Re: 3U Maths Question Thread
« Reply #274 on: June 29, 2016, 05:34:44 pm »
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Because the vessel is losing water that means the rate of change is negative right?

RuiAce

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Re: 3U Maths Question Thread
« Reply #275 on: June 29, 2016, 06:10:57 pm »
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Because the vessel is losing water that means the rate of change is negative right?

Sure

Or we could define positive as 'losing water' whereas negative is 'gaining water' ;)

140498

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Re: 3U Maths Question Thread
« Reply #276 on: June 29, 2016, 06:18:12 pm »
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Thanks heaps man, Sorry for all the dumb questions (in another setting where it is not an assessment I would not be second guessing myself)

Just quickly how was the most effective way you found studying for ext 1, just do past papers or was there something else.

RuiAce

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Re: 3U Maths Question Thread
« Reply #277 on: June 29, 2016, 06:22:20 pm »
+1
Thanks heaps man, Sorry for all the dumb questions (in another setting where it is not an assessment I would not be second guessing myself)

Just quickly how was the most effective way you found studying for ext 1, just do past papers or was there something else.

You're breaking all my own work and HSC policies if I'm doing an assignment for you.


Past papers all the way. That's for whatever maths you do.

140498

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Re: 3U Maths Question Thread
« Reply #278 on: June 29, 2016, 06:26:15 pm »
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No no no, i have my own answers I was just checking to see if I had gotten them right.
That is why they were relatively easy questions that I was asking, just to make sure. Sorry for not clearing that up

katherine123

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Re: 3U Maths Question Thread
« Reply #279 on: July 02, 2016, 10:00:08 am »
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how do i do last part (iii)

RuiAce

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Re: 3U Maths Question Thread
« Reply #280 on: July 02, 2016, 12:33:53 pm »
+1





This question just required you to interpret the question and realise "oh, have to go back to where I started". It's more of a deceptively easy question.

katherine123

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Re: 3U Maths Question Thread
« Reply #281 on: July 03, 2016, 02:10:16 am »
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first ques: not sure how to do last part  ie finding t   
second ques: not sure how to do last part

RuiAce

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Re: 3U Maths Question Thread
« Reply #282 on: July 03, 2016, 11:12:28 am »
+1
first ques: not sure how to do last part  ie finding t   
second ques: not sure how to do last part
As always, keep in mind that questions before the year 2001 do not accurately reflect the nature of the current HSC.






« Last Edit: July 03, 2016, 11:14:52 am by RuiAce »

RuiAce

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Re: 3U Maths Question Thread
« Reply #283 on: July 03, 2016, 11:30:48 am »
+1
first ques: not sure how to do last part  ie finding t   
second ques: not sure how to do last part




For the sake of graphing, by punching tan-1(2) into your calculator we find that alpha is approximately 1.107






Note: An alternate approach would've been to use an auxiliary angle transformation at the start. This is good, if you can do it by INSPECTION.

conic curve

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Re: 3U Maths Question Thread
« Reply #284 on: July 09, 2016, 07:45:20 pm »
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A friend of mine needed help with this question:

1. a. Consider the function f(x)=e^x/(1+e^x). Find f'(x) and deduce that f(x) is increasing for all x
b. State the range of f(x)
c. Find the inverse function f^-1(x)
d. Draw y-f(x) and y=f^-1(x) on the same diagram

« Last Edit: July 09, 2016, 07:48:01 pm by conic curve »