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    Hello, I'm stuck/confused with the following.

    Tan^2X+2tanx+1 express in terms of cotx. I think it's (cot^2x)+(1/2cotx)+1. But there's a devil in me trying to make believe its (cot^2x)+(2cotx)+1 - surely this can't be right? Which one is it
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    (Original post by Cool-Light)
    Hello, I'm stuck/confused with the following.

    Tan^2X+2tanx+1 express in terms of cotx. I think it's (cot^2x)+(1/2cotx)+1. But there's a devil in me trying to make believe its (cot^2x)+(2cotx)+1 - surely this can't be right? Which one is it
    I do not follow your argument
    would you be as kind as to post your working?
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    (Original post by Cool-Light)
    Hello, I'm stuck/confused with the following.

    Tan^2X+2tanx+1 express in terms of cotx. I think it's (cot^2x)+(1/2cotx)+1. But there's a devil in me trying to make believe its (cot^2x)+(2cotx)+1 - surely this can't be right? Which one is it
    2tanx is simply (2)x(tanx). You can then change (tanx) to (1/cotx) so you end up with (2)x(1/cotx) which is (2/cotx). I think

    (the 'x's outside the brackets being multiplication signs rather than the variable x)
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    (Original post by Cool-Light)
    Hello, I'm stuck/confused with the following.

    Tan^2X+2tanx+1 express in terms of cotx. I think it's (cot^2x)+(1/2cotx)+1. But there's a devil in me trying to make believe its (cot^2x)+(2cotx)+1 - surely this can't be right? Which one is it
    \tan x = \frac{1}{\cot x}
     \therefore \tan^{2} x + 2\tan x + 1 = \cot^{-2} x + 2 \cot^{-1} x + 1
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    (Original post by TeeEm)
    I do not follow your argument
    would you be as kind as to post your working?
    Ahhh, here's the original question manipulated by me. "Simplify the following expressions to a single term"

    Question: (tan^4x)+(2tan^x)+1, please don't solve it, it's one of my homework questions, I just need a hint. So I tried that up there in order to experiment and see where I get...
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    (Original post by morgan8002)
    \tan x = \frac{1}{\cot x}
     \therefore \tan^{2} x + 2\tan x + 1 = \cot^{-2} x + 2 \cot^{-1} x + 1
    Oh, so the devil turned out to be angel . Thank you for clearing the misconception
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    (Original post by Cool-Light)
    Ahhh, here's the original question manipulated by me. "Simplify the following expressions to a single term"

    Question: (tan^4x)+(2tan^x)+1, please don't solve it, it's one of my homework questions, I just need a hint. So I tried that up there in order to experiment and see where I get...
    look at post 4
    is what morgan8002 has written your question because what you have typed is ambiguous
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    Wait what...?
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    (Original post by TeeEm)
    look at post 4
    is what morgan8002 has written your question because what you have typed is ambiguous
    So there's more than one way of writing it?
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    (Original post by Cool-Light)
    Ahhh, here's the original question manipulated by me. "Simplify the following expressions to a single term"

    Question: (tan^4x)+(2tan^x)+1, please don't solve it, it's one of my homework questions, I just need a hint. So I tried that up there in order to experiment and see where I get...
    does tan^4x mean \tan^{4} x? what about 2tan^x?
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    (Original post by Cool-Light)
    So there's more than one way of writing it?



    Name:  straitjacket-vector-823041.jpg
Views: 71
Size:  64.1 KB



    NO!


    read this please

    http://www.thestudentroom.co.uk/show....php?t=2873737
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    Haha, that image made my day. I'll write it for u n upload
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    (Original post by Cool-Light)
    Haha, that image made my day. I'll write it for u n upload
    thanks
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    Hopefully it posted...
    Attached Images
     
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    (Original post by Cool-Light)
    Hopefully it posted...
    You can't legally derive the second expression.
    Think about how you can get it in a form where you can use the standard trig identities.
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    (Original post by morgan8002)
    You can't legally derive the second expression.
    Think about how you can get it in a form where you can use the standard trig identities.
    Omfg!! Thank you!!!!! I'm an idiot, if we were to factorise the image I uploaded without the illegal move we would get this:
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    (Original post by Cool-Light)
    Omfg!! Thank you!!!!! I'm an idiot, if we were to factorise the image I uploaded without the illegal move we would get this:
    I don't see an image, but factorising is the way to go. Do you see where to go now?
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    (Original post by morgan8002)
    You can't legally derive the second expression.
    Think about how you can get it in a form where you can use the standard trig identities.
    And true, I just did it to view my understanding from an easier perspective if that makes sense?
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    Did it upload
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    Sorry my net and my phone decides to freeze at certain points, [email protected]!
 
 
 
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