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March 29, 2024, 04:26:03 am

Author Topic: 3U Maths Question Thread  (Read 1230328 times)  Share 

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conic curve

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Re: 3U Maths Question Thread
« Reply #480 on: August 07, 2016, 10:10:15 am »
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Two mistakes in the last line.

1. You dropped off the 1/16
2. The x went missing inside the inverse tangent

Thanks

How do you do this (I think there's no inverse trig integration rule for it)

RuiAce

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Re: 3U Maths Question Thread
« Reply #481 on: August 07, 2016, 10:29:43 am »
+1
Thanks

How do you do this (I think there's no inverse trig integration rule for it)
Requires partial fractions. Not 3U material.

conic curve

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Re: 3U Maths Question Thread
« Reply #482 on: August 07, 2016, 10:31:50 am »
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Requires partial fractions. Not 3U material.

Thanks

What am I doing wrong

RuiAce

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Re: 3U Maths Question Thread
« Reply #483 on: August 07, 2016, 10:36:00 am »
+1

conic curve

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Re: 3U Maths Question Thread
« Reply #484 on: August 07, 2016, 10:52:59 am »
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jamonwindeyer

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Re: 3U Maths Question Thread
« Reply #485 on: August 07, 2016, 10:56:27 am »
+1
Thanks

How would  I do this?

Factorise!



That's an inverse sine integral  ;D you pull the 1 on root 3 out the front and then use your regular rule ;D

conic curve

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Re: 3U Maths Question Thread
« Reply #486 on: August 07, 2016, 11:05:00 am »
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Factorise!



That's an inverse sine integral  ;D you pull the 1 on root 3 out the front and then use your regular rule ;D

What happened to the dx?

jamonwindeyer

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Re: 3U Maths Question Thread
« Reply #487 on: August 07, 2016, 11:21:10 am »
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What happened to the dx?

Oh, it was just showing you the factorisation to apply, in the context of the integral:



Then apply the regular rule ;D

Spencerr

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Re: 3U Maths Question Thread
« Reply #488 on: August 07, 2016, 12:48:20 pm »
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Hey there, could some help explain to me how to graph these functions.

1. Cos (cos inverse x)
2. Cos (sin inverse x)
3.. Cos inverse (cos x)
4. Cos inverse (sinx)
5.. Tan inverse (tan x)
6. Tan (tan inverse x)

Sorry these are alot of graphs but I get really confused and I find it hard to wrap my head around these trigonometric inverse questions especially with all the restrictions.  Any other general tips in dealing with these questions will also be appreciated :)

Thanks

1st in HSC Eco 2016

RuiAce

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Re: 3U Maths Question Thread
« Reply #489 on: August 07, 2016, 01:04:43 pm »
+8
Hey there, could some help explain to me how to graph these functions.

1. Cos (cos inverse x)
2. Cos (sin inverse x)
3.. Cos inverse (cos x)
4. Cos inverse (sinx)
5.. Tan inverse (tan x)
6. Tan (tan inverse x)

Sorry these are alot of graphs but I get really confused and I find it hard to wrap my head around these trigonometric inverse questions especially with all the restrictions.  Any other general tips in dealing with these questions will also be appreciated :)

Thanks












More to come.
« Last Edit: August 06, 2017, 11:12:59 am by RuiAce »

RuiAce

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Re: 3U Maths Question Thread
« Reply #490 on: August 07, 2016, 01:15:12 pm »
+4










« Last Edit: August 06, 2017, 11:13:59 am by RuiAce »

RuiAce

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Re: 3U Maths Question Thread
« Reply #491 on: August 07, 2016, 01:29:43 pm »
+4










« Last Edit: August 06, 2017, 11:14:51 am by RuiAce »

Spencerr

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Re: 3U Maths Question Thread
« Reply #492 on: August 07, 2016, 03:22:04 pm »
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Thanks Rui, This is very well explained, clear and heaps helpful :)
1st in HSC Eco 2016

Neutron

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Re: 3U Maths Question Thread
« Reply #493 on: August 07, 2016, 06:39:35 pm »
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Hey hey! Thank you so much for the help with the other question ^^ I have returned with yet another one:

In a given lottery the probability that the jackpot prize is won is 0.013. Successive lottery draws are independent. The jackpot prize is initially 1, 000, 000 and increases by $250 000 each time the prize is not won. Find, correct to 5 decimal places, the probability that the jackpot prize will exceed $5 000 000 when it is finally won.

The answer just found the probability for it being won on the 17th draw (First draw when the prize is above 5 000 000) but don't you have to take into account the fact that the prize could be on on the 18th draw, 19th draw, 20th draw etc all the way till infinity? I don't understand how just finding the probability of it being won on the 17th draw is equal to finding the probability that the jackpot prize will exceed 5000 000 when it is finally won D:

Thank you legends!!

jamonwindeyer

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Re: 3U Maths Question Thread
« Reply #494 on: August 07, 2016, 07:02:29 pm »
+1
Hey hey! Thank you so much for the help with the other question ^^ I have returned with yet another one:

In a given lottery the probability that the jackpot prize is won is 0.013. Successive lottery draws are independent. The jackpot prize is initially 1, 000, 000 and increases by $250 000 each time the prize is not won. Find, correct to 5 decimal places, the probability that the jackpot prize will exceed $5 000 000 when it is finally won.

The answer just found the probability for it being won on the 17th draw (First draw when the prize is above 5 000 000) but don't you have to take into account the fact that the prize could be on on the 18th draw, 19th draw, 20th draw etc all the way till infinity? I don't understand how just finding the probability of it being won on the 17th draw is equal to finding the probability that the jackpot prize will exceed 5000 000 when it is finally won D:

Thank you legends!!

I agree with you Neutron! I'd be taking the sum of an infinite geometric series or something similar, where is the question from?  ;D