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    Find y dx when
    y= 3x^2 - x +6

    This was on integration question paper so do i differentiate this?
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    (Original post by Chelsea12345)
    To differentiate, do you take multiply by the power first then take 1 away from the power or do you take 1 from the power then multiply by the power?
    The former.
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    \frac{d}{dx} (ax^n) = anx^{n-1}

    That is multiply by the original power, then reduce the power by 1.
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    (Original post by Chelsea12345)
    To differentiate, do you take multiply by the power first then take 1 away from the power or do you take 1 from the power then multiply by the power?
    Multiply then take away. In other terms,  \frac{d}{dx} [x^n] = nx ^{n-1} , where n is a constant.


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    (Original post by Chelsea12345)
    To differentiate, do you take multiply by the power first then take 1 away from the power or do you take 1 from the power then multiply by the power?
    the order doesn't matter, at least for simple differentiation:

    y=ax^n => dy/dx = nax^(n-1)
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    (Original post by Chelsea12345)
    Find y dx when
    y= 3x^2 - x +6

    This was on integration question paper so do i differentiate this?
    No you need to integrate. Please don't change your questions like this. It makes the thread impossible to follow.
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    (Original post by Mr M)
    No you need to integrate. Please don't change your questions like this. It makes the thread impossible to follow.
    Apologies! And why integrate? Aren't you finding what the equation is after it has been differentiated since integration is the opposite of differentiation? I'm a bit confused on this.
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    (Original post by Chelsea12345)
    Apologies! And why integrate? Aren't you finding what the equation is after it has been differentiated since integration is the opposite of differentiation? I'm a bit confused on this.
    I'm assuming the question asked you to find \int y \, dx ? If this is the case, replace y in the integral with the quadratic and then follow the instruction given by the integration symbol to integrate.
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    (Original post by Mr M)
    I'm assuming the question asked you to find \int y \, dx ? If this is the case, replace y in the integral with the quadratic and then follow the instruction given by the integration symbol to integrate.
    yes it was. Thankyou, i think i get what the question is asking now.
 
 
 

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