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    (Original post by Indeterminate)
    Your integral should be

    \displaystyle 4 \int_{\frac{\pi}{2}}^0 \sin^2 t \cos t \ dt

    which does give 4/3

    Note that x is the larger value when t=0.
    is sin3x / 3 -sint right or worng? and how come the smaller value of 0 is on the top
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    (Original post by laurawoods)
    is sin3x / 3 -sint right or worng? and how come the smaller value of 0 is on the top
    It's because it corresponds to the larger of the two values of x.

    The integral evaluates to

    \displaystyle -\frac{4}{3} \sin^3 t +C

    Ignoring the +C, evaluating between 0 and pi over 2 gives the required answer.
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    (Original post by laurawoods)
    hello , i don't see how that could potentially work because if you diff 2x+3 you get just 2 , isn't it so? So it definitely cannot be forming that pattern of diff/ original function , isn't it so? Please correct me...
    use substitution, let u= 2x+3 so 2x= u-3
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    (Original post by Indeterminate)
    It's because it corresponds to the larger of the two values of x.

    The integral evaluates to

    \displaystyle -\frac{4}{3} \sin^3 t +C

    Ignoring the +C, evaluating between 0 and pi over 2 gives the required answer.
    Hello there ! how are you today? Do you have access to the MEI website , if u don't mind me asking?
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    (Original post by laurawoods)
    Hello there ! how are you today? Do you have access to the MEI website , if u don't mind me asking?
    Fine, thanks How do you mean?
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    (Original post by Indeterminate)
    Fine, thanks How do you mean?
    Hello there, I just meant access to the website. I wanted to do practice from there to improve on these concepts....
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    (Original post by Indeterminate)
    Fine, thanks How do you mean?
    Is the 'connected rates of change' and setting up simple diff equations pretty much the same idea? how are they similar and how r they different>
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    (Original post by laurawoods)
    Hello there, I just meant access to the website. I wanted to do practice from there to improve on these concepts....
    Specifically, what are you after? Papers, revision sheets and stuff?
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    (Original post by Indeterminate)
    Specifically, what are you after? Papers, revision sheets and stuff?
    hello there , I am after some revision sheets specifically for C4? thanks any help from ur side would be massively useful! I don't know if MEI and Integral Maths are the same or not?
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    (Original post by Indeterminate)
    Specifically, what are you after? Papers, revision sheets and stuff?
    do you think you would be able to help me with the MEI i was requesting? thanks!
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    (Original post by laurawoods)
    do you think you would be able to help me with the MEI i was requesting? thanks!
    Well, I've not found anything useful on the MEI website, but a quick google search took me to

    http://www.london-oratory.org/maths/...dex/index.html

    These questions tend to be harder than the Edexcel ones, so you should look to be able to tackle each question on each sheet for each topic. There are loads of sheets for vectors/integration.

    Have fun!
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    (Original post by Indeterminate)
    Well, I've not found anything useful on the MEI website, but a quick google search took me to

    http://www.london-oratory.org/maths/...dex/index.html

    Have fun!
    There is no fun in doing maths questions for me!

    cool thanks! btw pls can you help me with this:

    http://www.london-oratory.org/maths/...s/E4Qdif_E.pdf

    I was trying to do question 7b) but got a bit stuck ! do we have to solve diff equations to do that question or does this question come under the volume of revolution thing? thanks!
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    (Original post by laurawoods)
    There is no fun in doing maths questions for me!

    cool thanks! btw pls can you help me with this:

    http://www.london-oratory.org/maths/...s/E4Qdif_E.pdf

    I was trying to do question 7b) but got a bit stuck ! do we have to solve diff equations to do that question or does this question come under the volume of revolution thing? thanks!
    Well, what's the volume after 5 seconds?

    Once you've found that, you need to find h by rearranging and substitute to the V formula. Now, find

    \dfrac{dV}{dh}

    Hint:

    \dfrac{dV}{dt} = \dfrac{dV}{dh} \times \dfrac{dh}{dt}

    You're looking for dh/dt, which is the rate of change of the depth.
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    (Original post by Indeterminate)
    Well, what's the volume after 5 seconds?

    Once you've found that, you need to find h by rearranging and substitute to the V formula. Now, find

    \dfrac{dV}{dh}

    Hint:

    \dfrac{dV}{dt} = \dfrac{dV}{dh} \times \dfrac{dh}{dt}

    You're looking for dh/dt, which is the rate of change of the depth.
    hello just a quick question out of interest , for oxbridge , so mathematicians have to do step exams or is it just an interview?
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    (Original post by laurawoods)
    hello just a quick question out of interest , for oxbridge , so mathematicians have to do step exams or is it just an interview?
    For Cambridge interview and two STEP papers.

    For Oxford, entrance test and interview.
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    (Original post by Mr M)
    For Cambridge interview and two STEP papers.

    For Oxford, entrance test and interview.
    ok cool ! if u don't mind me asking, did u get into oxbridge ?
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    (Original post by laurawoods)
    ok cool ! if u don't mind me asking, did u get into oxbridge ?
    I didn't try. I wanted to go to London (I had dreams of making it big in the music business) so attended UCL.
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    (Original post by Mr M)
    I didn't try. I wanted to go to London (I had dreams of making it big in the music business) so attended UCL.
    do u regret not applying to oxbridge?
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    (Original post by Mr M)
    I didn't try. I wanted to go to London (I had dreams of making it big in the music business) so attended UCL.
    Did u always want to be a Maths teacher or did u decide it later on in life?
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    (Original post by laurawoods)
    do u regret not applying to oxbridge?
    Well it hasn't made the slightest difference to my life at all. I did put Cambridge as my second choice for postgraduate teacher training but I was offered my first choice (the local provider) and this made sense as my children were settled in school.
 
 
 
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