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    https://www.biochemtuition.com/wp-co...rentiation.pdf

    Exercise 4C. Question 2. I don't really understand how to do it, would appreciate some help. Thanks
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    "the site cannot provide a secure connection"

    could you scan the question *?*
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    (Original post by Paranoid_Glitch)
    https://www.biochemtuition.com/wp-co...rentiation.pdf

    Exercise 4C. Question 2. I don't really understand how to do it, would appreciate some help. Thanks
    Differentiate it, find the gradient at x=2, then construct the tangent line by using y-y_1=m(x-x_1)

    Also turn that mixed fraction into an improper one, for the sake of simplicity.
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    Remember that if you have a function f then f'(x) is, by definition, the gradient of the tangent line to f drawn at x.
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    (Original post by RDKGames)
    Differentiate it, find the gradient at x=2, then construct the tangent line by using y-y_1=m(x-x_1)

    Also turn that mixed fraction into an improper one, for the sake of simplicity.
    Thanks. Though how do i differentiate it. I ended up with y * (in 2 -in 2) which is definitely wrong.
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    (Original post by Paranoid_Glitch)
    Thanks. Though how do i differentiate it though. I ended up with y * (in 2 -in 2) which is definitely wrong.
    If y = 2^x + 2^{-x} then y = e^{x \ln 2} + e^{-x \ln 2} so

    y' = \ln 2 e^{x \ln 2} - \ln 2 e^{-x \ln 2} = 2^x \ln 2  - 2^{-x} \ln 2 = \ln2 (2^x - 2^{-x})

    not sure where you're getting that you're getting frmo.
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    (Original post by Paranoid_Glitch)
    Thanks. Though how do i differentiate it though. I ended up with y * (in 2 -in 2) which is definitely wrong.
    You can use substitution u=2^x.

    Do you know how to differentiate u with respect to x?
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    (Original post by RDKGames)
    You can use substitution u=2^x.

    Do you know how to differentiate u with respect to x?
    Yeah it worked. Thanks. (With chain rule, right?)
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    (Original post by Paranoid_Glitch)
    Yeah it worked. Thanks. (With chain rule, right?)
    Chain rule is the overall method, yeah, but differentiation of u wrt x would require implicit differentiation.
 
 
 
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