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March 29, 2024, 09:03:11 am

Author Topic: 3U Maths Question Thread  (Read 1230397 times)  Share 

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katherine123

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Re: 3U Maths Question Thread
« Reply #375 on: July 28, 2016, 10:36:02 am »
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how to find domain of y= inverse sin(1-x^2)

RuiAce

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Re: 3U Maths Question Thread
« Reply #376 on: July 28, 2016, 10:43:11 am »
+1
how to find domain of y= inverse sin(1-x^2)





conic curve

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Re: 3U Maths Question Thread
« Reply #377 on: July 31, 2016, 09:35:45 am »
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Sorry but I've got a mind blank right now

How do I differentiate y=2sin^-1 squareroot of x

Thanks

RuiAce

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Re: 3U Maths Question Thread
« Reply #378 on: July 31, 2016, 09:48:25 am »
+1

conic curve

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Re: 3U Maths Question Thread
« Reply #379 on: July 31, 2016, 09:53:58 am »
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Thanks

Do I chain rule everything with a coeffiient in front of the inverse trig?

I tend to get confused with coefficients and differentating inverse trig

Similar to how I think 2tantheta=tan2theta

RuiAce

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Re: 3U Maths Question Thread
« Reply #380 on: July 31, 2016, 10:11:18 am »
+1
Thanks

Do I chain rule everything with a coeffiient in front of the inverse trig?

I tend to get confused with coefficients and differentating inverse trig

Similar to how I think 2tantheta=tan2theta
What do you mean?

I used the chain rule because of the stupid square root inside the inverse sine, not the coefficient

conic curve

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Re: 3U Maths Question Thread
« Reply #381 on: July 31, 2016, 10:25:11 am »
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What do you mean?

I used the chain rule because of the stupid square root inside the inverse sine, not the coefficient

So if you had y=2 squareroot of (sin^-1x) would you still have to use the chain rule?

jakesilove

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Re: 3U Maths Question Thread
« Reply #382 on: July 31, 2016, 10:34:51 am »
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So if you had y=2 squareroot of (sin^-1x) would you still have to use the chain rule?

That's a totally different question. The general form for differentiating inverse sin is


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massive

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Re: 3U Maths Question Thread
« Reply #383 on: July 31, 2016, 11:21:18 am »
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Could they ask us to sketch a graph of that function^
And how would you even sketch that graph??

RuiAce

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Re: 3U Maths Question Thread
« Reply #384 on: July 31, 2016, 11:25:14 am »
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Could they ask us to sketch a graph of that function^
And how would you even sketch that graph??
In Extension 2, of course

In Extension 1, highly unlikely. The domain can be found because all that you're taught in the 3U course is sufficient to find it. But the graph itself is something you would have to be guided through, i.e. stationary points etc.

conic curve

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Re: 3U Maths Question Thread
« Reply #385 on: July 31, 2016, 06:27:41 pm »
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For this question (that I have attached below) why do we take 3 outside of the integral rather than -3 (look at 2nd step)

jakesilove

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Re: 3U Maths Question Thread
« Reply #386 on: July 31, 2016, 06:30:20 pm »
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For this question (that I have attached below) why do we take 3 outside of the integral rather than -3 (look at 2nd step)

The reason they take 3 instead of -3 is because integration to inverse cos requires a negative coefficient.



They could just have easily taken out -3, and integrated to sin instead of cos. Hope that makes sense!

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Re: 3U Maths Question Thread
« Reply #387 on: July 31, 2016, 06:58:38 pm »
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jamonwindeyer

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Re: 3U Maths Question Thread
« Reply #388 on: July 31, 2016, 07:29:11 pm »
+1
The reason they take 3 instead of -3 is because integration to inverse cos requires a negative coefficient.
They could just have easily taken out -3, and integrated to sin instead of cos. Hope that makes sense!
Jake



For clarity conic, both answers are correct, just depends what you want to do with it  ;D

conic curve

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Re: 3U Maths Question Thread
« Reply #389 on: July 31, 2016, 08:48:36 pm »
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For clarity conic, both answers are correct, just depends what you want to do with it  ;D

Thanks Jamon

Anyways I am confused with the following inverse trig integration questions

For the first Integral I attached below, why do we remove 1/2 out to the front?

Ignore the second because I believe that this is a similar principle to the first

For the third why do we use polynomial long division?

Also could someone please help me with the second attached file and explain the theory behind this because I'm not too sure what the underlying theory behind this is (I mean I've seen the working to it but I don't understand what's going on)

Thanks
« Last Edit: July 31, 2016, 08:55:09 pm by conic curve »