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    I'm new to this so don't slaughter me.

    x^n -> nx^(n-1)

    So you do that throughout, but in an example I was looking at,

    x^2 +5x -6

    becomes

    2x + 5

    I get the 5 and 2x part, but how can the 6 go, the power becomes zero, but that will turn the 1x-6 into a 1 ? Clearly not, what am I missing?
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    6=6*1=6x^0
    Differentiate: 0*6x^{-1} = 0
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    (Original post by Math12345)
    6=6*1=6x^0
    Differentiate: 0*6x^{-1} = 0
    Thank you
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    (Original post by SuchBants)
    I'm new to this so don't slaughter me.

    x^n -> nx^(n-1)

    So you do that throughout, but in an example I was looking at,

    x^2 +5x -6

    becomes

    2x + 5

    I get the 5 and 2x part, but how can the 6 go, the power becomes zero, but that will turn the 1x-6 into a 1 ? Clearly not, what am I missing?
    A good way to understand it is to look at the geometrical interpretation:
    Consider a straight line graph  y=mx+c , then  \dfrac{dy}{dx} is the gradient of that graph (or any graph) at a given point x. If we vary c, i.e. change it to be larger or smaller, we just translate the graph up parallel to the y axis hence we are not effecting the gradient i.e. the +c cant affect the derivative.
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    In accordance with the above - the derivative measures the gradient of a curve at any given point, and the gradient of the line y = c is 0 (it's just a straight line).
 
 
 
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