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    Hi, I've got a quick question:

    What is the derivative of sec^2(x) [sec squared x] :confused:

    Thanks!
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    Using the product rule you differentiate the outside which is 2secx and then times the differential of secx which is secxtanx so the answer is 2sec^2xtanx.
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    (Original post by rockiee)
    Hi, I've got a quick question:

    What is the derivative of sec^2(x) [sec squared x] :confused:

    Thanks!
    Think u have to use the chain rule.

    y=u^2 u=secx
    dy/du =2u du/dx=tanxsecx
    dy/dx= dy/du x du/dx (dy/du multiplied by du/dx)
    dy/dx = 2u times tanxsecx substitute u=secx

    dy/dx= 2secx tanxsecx = 2tanxsec^2x
    Hope thats right.
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    Beat me to it, but I've added it as example 4 here:

    http://wikinotes.cdpuk.net/wiki/The_chain_rule

    with a little more explanation

    -Chris
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    Doh! I meant the chain rule
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    (Original post by rockiee)
    Hi, I've got a quick question:

    What is the derivative of sec^2(x) [sec squared x] :confused:

    Thanks!
    For some reason I feel you meant the integral of sec^2(x) ?

    If so, its quite hard to do, and you would just differentiate tanx to show its the integral of sec^2(x)
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    Thanks everyone! I also managed to get the answer through using the trig identity of sec^2(x) i.e. 1+tan^2(x) and I got the same answer as above.

    Thanks for all your help!
 
 
 
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