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    Hiya,

    I came across this really uncommon differentiation question and i'm not sure how to do it. Can any of you give me a hand please?




    i've worked out (they are correct cos i've checked the book's answers):

    \frac{dy}{dx} = -3{e^x}sin3x + {e^x}cos3x

    and

    \frac{d^2y}{dx^2} = 6{e^x}sin3x - 8{e^x}cos3x

    thanks a lot!!
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    the thing is, do you just show it by multiplying your dy/dx by 2 and your 'y' equation by 10? But i don't feel that it's the right way to show how i have reached the conclusion.........
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    yes just bung in your y, dy/dx and d2y/dx2 to the equation as you suggested and cancel it down to show it is equal to 0.
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    thanks...i thought that would be a bit too easy at first lol
 
 
 
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