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same differentiation question but using different methods Watch

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    Hi,

    There's a differentiation question that requires you to solve y=\frac{e^x}{x}. You can see straight away that the quotient rule should be used but I decided to rewrite the equation as y=x^{-1}{e^x} and used the product rule to solve it.

    answer using product rule: \frac{-e^x}{x^2} + \frac{e^x}{x}

    using quotient rule: \frac{e^x(x-1)}{x^2}

    The answers came out totally different..(or are they in fact the same answers written differently?!)....but i thought i remembered that it's fine to rewrite the equation and solve it with the product rule......is it really not allowed to do something like this?

    thanks.
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    They're the same (multiply the right hand fraction by x/x and combine)
 
 
 
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