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    Evaluate the integral;
     \displaystyle\int \cosh^2 x\ dx
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    (Original post by InternetGangster)
    Evaluate the integral;
     \displaystyle\int \cosh^2 x\ dx
    Two main ways.

    Express it in exponential form

    OR

    Use an identity to express cosh^2 x in terms of cosh 2x.
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    (Original post by Mr M)
    Two main ways.

    Express it in exponential form

    OR

    Use an identity to express cosh^2 x in terms of cosh 2x.
    [(e^x + e^-x)/ 2 ]^2 and then expand and then simple integration right :?
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    (Original post by Mihael_Keehl)
    [(e^x + e^-x)/ 2 ]^2 and then expand and then simple integration right :?
    I do not think he cares after 2 years ....
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    (Original post by TeeEm)
    I do not think he cares after 2 years ....
    I care deeply.
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    (Original post by Mihael_Keehl)
    [(e^x + e^-x)/ 2 ]^2 and then expand and then simple integration right :?
    I don't know man. Maybe by 2017 I will have the answer
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    (Original post by TeeEm)
    I do not think he cares after 2 years ....
    Maybe

    (Original post by Mr M)
    I care deeply.
    Haha +1
    (Original post by InternetGangster)
    I don't know man. Maybe by 2017 I will have the answer
    Keep calm and carry on integrating.

    Just out of interest is this FP3? Seems to simple for FP3 but I think hyperbolic identities is first covered in FP3.
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    (Original post by InternetGangster)
    I don't know man. Maybe by 2017 I will have the answer
    cosh^2 x = 1/2cosh2x + 1/2 using hyperbolic functions manipulation from those found in the formula booklet

    1/2cosh2x +1/2 dx = 1/4sinh2x +1/2 x +c

    I created an account just to answer your question btw
 
 
 
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