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March 29, 2024, 12:14:14 pm

Author Topic: 3U Maths Question Thread  (Read 1230475 times)  Share 

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RuiAce

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Re: 3U Maths Question Thread
« Reply #750 on: October 08, 2016, 03:13:01 pm »
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Hey,
I know this is probably really really simple but i wasn't in class when this was covered so i was just wondering if someone could explain how to find the value of this question to me?

Blissfulmelodii

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Re: 3U Maths Question Thread
« Reply #751 on: October 08, 2016, 03:16:08 pm »
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ohh yes it's that! Sorry I typed it wrong.
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Music 1 | Biology | Society and Culture | Spanish Beginners | Math ext 1 & 2 | English Advanced | English ext 1 & 2

RuiAce

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Re: 3U Maths Question Thread
« Reply #752 on: October 08, 2016, 03:22:49 pm »
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Blissfulmelodii

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Re: 3U Maths Question Thread
« Reply #753 on: October 08, 2016, 03:26:02 pm »
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ahh okay, that makes sense.
Is there a proof for that identity or is it just something to memorise?
Thank you!
--HSC subjects--
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RuiAce

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Re: 3U Maths Question Thread
« Reply #754 on: October 08, 2016, 03:28:08 pm »
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ahh okay, that makes sense.
Is there a proof for that identity or is it just something to memorise?
Thank you!
There is most certainly a proof for it but memorising it is well beyond 3U.

Blissfulmelodii

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Re: 3U Maths Question Thread
« Reply #755 on: October 08, 2016, 04:04:11 pm »
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14 past papers in and I currently have a stack of questions that I am stumped on, so i apologise in advance for the spam that will most likely occur.
Can someone please explain how to solve this question from the 2008 HSC paper that I have attached below.
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Music 1 | Biology | Society and Culture | Spanish Beginners | Math ext 1 & 2 | English Advanced | English ext 1 & 2

RuiAce

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Re: 3U Maths Question Thread
« Reply #756 on: October 08, 2016, 04:27:04 pm »
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14 past papers in and I currently have a stack of questions that I am stumped on, so i apologise in advance for the spam that will most likely occur.
Can someone please explain how to solve this question from the 2008 HSC paper that I have attached below.
If they're all past HSC papers, look at the answers first in the future. You're more than free to address any confusion with the answers though.




________________________________________


________________________________________
« Last Edit: October 08, 2016, 04:51:09 pm by RuiAce »

Blissfulmelodii

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Re: 3U Maths Question Thread
« Reply #757 on: October 08, 2016, 04:49:20 pm »
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If they're all past HSC papers, look at the answers first in the future. You're more than free to address any confusion with the answers though.




________________________________________


________________________________________


When I said stumped I mean not even the worked solutions on BOSTES makes sense to me lol.
Thank you for the explanation, i definitely needed that! It took me a while to understand the second part but I think i get it now. Thanks again  :)
--HSC subjects--
Music 1 | Biology | Society and Culture | Spanish Beginners | Math ext 1 & 2 | English Advanced | English ext 1 & 2

RuiAce

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Re: 3U Maths Question Thread
« Reply #758 on: October 08, 2016, 04:52:35 pm »
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When I said stumped I mean not even the worked solutions on BOSTES makes sense to me lol.
Thank you for the explanation, i definitely needed that! It took me a while to understand the second part but I think i get it now. Thanks again  :)
BOSTES solutions don't always make sense because they just spit it out. Hence the link - solutions written by other sources are usually clearer.

The best solutions come from the MANSW published books but those aren't for free

But as stated above, feel free to come for help with clarifying the answers anytime
« Last Edit: October 08, 2016, 04:55:41 pm by RuiAce »

WLalex

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Re: 3U Maths Question Thread
« Reply #759 on: October 11, 2016, 01:41:45 pm »
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can someone please help me out with part ii...do not like SHM at all


Thanks
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RuiAce

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Re: 3U Maths Question Thread
« Reply #760 on: October 11, 2016, 01:54:20 pm »
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can someone please help me out with part ii...do not like SHM at all


Thanks







WLalex

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Re: 3U Maths Question Thread
« Reply #761 on: October 11, 2016, 02:55:04 pm »
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ah, perfect. Thanks Rui
"You don't want to look back and know you could have done better"

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anotherworld2b

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Re: 3U Maths Question Thread
« Reply #762 on: October 13, 2016, 08:28:49 pm »
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Can i Get help with this question please?

jakesilove

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Re: 3U Maths Question Thread
« Reply #763 on: October 13, 2016, 09:11:19 pm »
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Can i Get help with this question please?

Hey! So, the question is basically asking us to find the stationary point (ie. the minimum value), and then the x value for which this will occur. Naturally, we employ calculus for this!

Our expanded equation is



So, we start by finding the derivative



If we set this equal to zero, and multiply out our denominators, we can use the quadratic formula to find solutions. We find that the first value for x is



This is where the maximum sag occurs; sub it back into the original equation to get the maximum sag!

Let me know if I can clarify anything

Jake
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anotherworld2b

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Re: 3U Maths Question Thread
« Reply #764 on: October 13, 2016, 10:14:26 pm »
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thank you for you help
I got confused on how to multiply out the denominators and use the quadratic formula to find solutions. How do you do this?  :o

Hey! So, the question is basically asking us to find the stationary point (ie. the minimum value), and then the x value for which this will occur. Naturally, we employ calculus for this!

Our expanded equation is



So, we start by finding the derivative



If we set this equal to zero, and multiply out our denominators, we can use the quadratic formula to find solutions. We find that the first value for x is



This is where the maximum sag occurs; sub it back into the original equation to get the maximum sag!

Let me know if I can clarify anything

Jake