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    In the picture I cannot get the expression I have differentiated into the form they want in the question ... Any ideas? thanks
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    missing an X after 1/2(2)-insert X-^-1/2
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    (Original post by Booyah)
    missing an X after 1/2(2)-insert X-^-1/2
    opps my bad! i am still unsure of how to do it though :/
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    (Original post by madfish)
    opps my bad! i am still unsure of how to do it though :/
    write X^-1/2 - 9X^-5/2 into fractions. See what you can do from there
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    (Original post by Booyah)
    write X^-1/2 - 9X^-5/2 into fractions. See what you can do from there
    euggghh!!!! I cannot do it
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    (Original post by madfish)
    euggghh!!!! I cannot do it
    the answer's denominator is X^2X^1/2

    which is X^5/2 as 2+ 1/2 is 5/2 which links to 9X^5/2

    Now do you have any ideas on what to do for X^-0.5?

    And don't worry, it is just practice, I averaged Cs+D's all year long for maths but with enough practice I got an A in the actual exam
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    (Original post by Booyah)
    the answer's denominator is X^2X^1/2

    which is X^5/2 as 2+ 1/2 is 5/2 which links to 9X^5/2

    Now do you have any ideas on what to do for X^-0.5?

    And don't worry, it is just practice, I averaged Cs+D's all year long for maths but with enough practice I got an A in the actual exam
    I really have no idea about this question sorry I sound so stupid

    yea these are the rotten last questions on the differentiation chapter.. and thanks so much !
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    (Original post by madfish)
    I really have no idea about this question sorry I sound so stupid

    yea these are the rotten last questions on the differentiation chapter.. and thanks so much !
    Alright then, this is a GCSE skill which derives on multiplying something by 1 doesn't change the value.

    Take 1/2 if we multiply it by 4/4 it becomes 4/8 which is still 1/2

    So if we use this but with X^2/X^2 and multiply X^-1/2 we will still get X^1/2 but in the form X^2/X^5/2 which is infact:

    X^2/(X^2)(X^0.5). Now you can subtract the other fraction 9/(X^2)(X^0.5)

    Quote any part you don't understand (I can't use that maths number thingy though...)
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    (Original post by Booyah)
    Alright then, this is a GCSE skill which derives on multiplying something by 1 doesn't change the value.

    Take 1/2 if we multiply it by 4/4 it becomes 4/8 which is still 1/2

    So if we use this but with X^2/X^2 and multiply X^-1/2 we will still get X^1/2 but in the form X^2/X^5/2 which is infact:

    X^2/(X^2)(X^0.5). Now you can subtract the other fraction 9/(X^2)(X^0.5)

    Quote any part you don't understand (I can't use that maths number thingy though...)
    Okay I am at the part where I have differentiated to get 2/x^7/2 + 6/x^3/2

    where do i go from here?
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    (Original post by madfish)
    Okay I am at the part where I have differentiated to get 2/x^7/2 + 6/x^3/2

    where do i go from here?
    The differential is X^-0.5 - 9X^-2.5

    as the powers are negative
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    Name:  img019.jpg
Views: 122
Size:  106.3 KBHere you go! That integral sign meant to be dy/dx :P I don't know why I did that D:
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    (Original post by Lifestalker)
    Name:  img019.jpg
Views: 122
Size:  106.3 KBHere you go! That integral sign meant to be dy/dx :P I don't know why I did that D:
    thanks very much
    do you think that is a hard question for as level? bearing in mind this is as level!
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    (Original post by madfish)
    thanks very much
    do you think that is a hard question for as level? bearing in mind this is as level!
    Pretty standard differentiation question tbh, something you'd expect in the exam for algebra differentiation, they can't just give you simple ones otherwise that's easy marks :P
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    (Original post by Lifestalker)
    Name:  img019.jpg
Views: 122
Size:  106.3 KBHere you go! That integral sign meant to be dy/dx :P I don't know why I did that D:
    one question... how do you get the numerator of 9 to be that? I get it to be (sqrtx)^5
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    Yeah, I'm at your level too!
    I, personally, didn't find it difficult, but I can see where you would have trouble (it's pretty weird changing the denominator, actually).
    I think I would've had trouble without it saying "if f'(x) = whatever".
    If you practice enough, it'll become second nature, so, at the moment, it may seem difficult, but give it time
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    (Original post by Robbie242)
    Pretty standard differentiation question tbh, something you'd expect in the exam for algebra differentiation, they can't just give you simple ones otherwise that's easy marks :P
    dude, that is harder than standard questions... just saying
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    The numerator 9?

    I did 6*(-[3/2])
    or rather: 6*(-1.5) = -9
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    (Original post by madfish)
    dude, that is harder than standard questions... just saying
    Well it is unlikely they'll say y=3x^4+3x^3+2x+1 find the maximum value that's like c2 differentiation exercise 9b) stuff like 9c) 9d) and mixed exercises they're more likely to ask. Regardless though if your not familiar with indices and other things used here it can be tough
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    (Original post by Lifestalker)
    The numerator 9?

    I did 6*(-[3/2])
    or rather: 6*(-1.5) = -9
    got it now dude, cheers for that! Love it when someone puts the solutions up! Makes me learn it a lot easier
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    (Original post by Robbie242)
    Well it is unlikely they'll say y=3x^4+3x^3+2x+1 find the maximum value that's like c2 differentiation exercise 9b) stuff like 9c) 9d) and mixed exercises they're more likely to ask. Regardless though if your not familiar with indices and other things used here it can be tough
    I am doing these questions from a textbook I bought, not the edexcel one... I have done all the edexcel ones they are quite easy tbh lol

    and yea, I am going to practice C1 all day tomorrow do all then indicies questions etc
 
 
 
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