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Differentiate y = 3sin^2 x e^5x – 1 with respect to x Watch

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    Can anyone differentiate y = 3sin^2 x e^5x – 1 with respect to x? I have completed the question, however as i don't have the answer to refer to i am not sure its 100% correct.

    Any help?
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    (Original post by zeesus699)
    Can anyone differentiate y = 3sin^2 x e^5x – 1 with respect to x? I have completed the question, however as i don't have the answer to refer to i am not sure its 100% correct.

    Any help?
    Amended due to ambiguous notation:

    http://www.wolframalpha.com/input/?i...E2x+e%5E(5x-1)
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    Absolute legend!
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    (Original post by zeesus699)
    Absolute legend!
    Remember the website. It is great for checking your work.
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    It turns out my working out are wrong, and i can't seem to find the correct method of producing that answer. Any guidance?
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    (Original post by zeesus699)
    It turns out my working out are wrong, and i can't seem to find the correct method of producing that answer. Any guidance?
    Post your working and someone will tell you where the error is.
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    So far, using the product rules.

    y = 3sin^2 x e^5x – 1
    U=e^5x-1
    V=3sin^2x

    du/dv= e^5x-1
    dv/du=6sin(x)cos(x)

    Dy/dx= u*(dv/du) + V*(du/dx)

    Dy/dx= e^5x-1 6sin(x)cos(x) + 3sin^2x e^5x-1

    Any help in where i am going wrong? I am relatively new to doing this level of differentiating.
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    (Original post by zeesus699)
    So far, using the product rules.

    y = 3sin^2 x e^5x – 1
    U=e^5x-1
    V=3sin^2x

    du/dv= e^5x-1
    dv/du=6sin(x)cos(x)

    Dy/dx= u*(dv/du) + V*(du/dx)

    Dy/dx= e^5x-1 6sin(x)cos(x) + 3sin^2x e^5x-1

    Any help in where i am going wrong? I am relatively new to doing this level of differentiating.
    Ok I can see the problem. Your notation was ambiguous. I interpreted your question as e^{(5x)}-1 rather than e^{(5x-1)}. I'll amend the link to Wolfram. Also your \frac{du}{dx} (NOT \frac{du}{dv}) is wrong.
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    (Original post by Mr M)
    Ok I can see the problem. Your notation was ambiguous. I interpreted your question as e^{(5x)}-1 rather than e^{(5x-1)}. I'll amend the link to Wolfram. Also your \frac{du}{dx} (NOT \frac{du}{dv}) is wrong.
    Much appreciated, however I have already amended it beforehand. Oh, and the "du/dv" was a typing error. Thanks for the correction.

    I am having trouble trying to figure out how to differentiate more complex trigonometric functions more than anything, as my knowledge of them is not 100%. How would I go about trying to differentiate this?

    Thanks
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    (Original post by zeesus699)
    Much appreciated, however I have already amended it beforehand. Oh, and the "du/dv" was a typing error. Thanks for the correction.

    I am having trouble trying to figure out how to differentiate more complex trigonometric functions more than anything, as my knowledge of them is not 100%. How would I go about trying to differentiate this?

    Thanks
    The trigonometric bit was correct. The exponential bit was incorrectly differentiated.

    \diplaystyle \frac{d}{dx} e^{ax+b} = a e^{ax+b}
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    Excuse my bad hand writing
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    (Original post by Gurtajs)
    ...
    Please read the Forum Rules at the top of the Maths Forum. Full worked solutions are not allowed. Just give hints please.
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    (Original post by Olmeister)
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    Please read the Forum Rules at the top of the Maths Forum. Full worked solutions are not allowed. Just give hints please.
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    (Original post by Mr M)
    Please read the Forum Rules at the top of the Maths Forum. Full worked solutions are not allowed. Just give hints please.
    I have never seen these rules, and apologise as I did not realise that this is what the standards are. However, I feel that personally when I do post a question on here it is easier to get someone else's working and then compare it to my own. It gives me practice as well as the person asking the question.

    I will keep to only posting hints in the future.
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    (Original post by Olmeister)
    I have never seen these rules, and apologise as I did not realise that this is what the standards are. However, I feel that personally when I do post a question on here it is easier to get someone else's working and then compare it to my own. It gives me practice as well as the person asking the question.

    I will keep to only posting hints in the future.
    Much appreciated for the working out. I share your view on reviewing other peoples working and then comparing, it has just helped me remove a mental block that was slowing down my progress for my up and coming exam on Monday.
 
 
 
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