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    • Thread Starter
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    Show that tanx+ tan^-1x =tanx/sin^2x
    What i DID WAS let tanx= sinx/cosx

    but I'm stuck there
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    RDKGames


    Put your degree to good use and help a brother out
    • Thread Starter
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    I get really close by getting to
    sinx/cosx + cosx/sinx
    I then made cosx= sinx/tanx
    I get the sin^2 on the bottom but the top is wrong
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    (Original post by mariejuana)
    I get really close by getting to
    sinx/cosx + cosx/sinx
    I then made cosx= sinx/tanx
    I get the sin^2 on the bottom but the top is wrong
    sinx/cosx + cosx/sinx = (sin^2x + cos^2x)/sinxcosx by making both fractions have a common denominator.

    The top =1 by identity.

    Now divide top and bottom by cosx, then multiply top and bottom by sinx
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    \frac{sin(x)}{cos(x)}+\frac{cos(  x)}{sin(x)}=\frac{sin(x)sin(x)}{  cos(x)sin(x)}+\frac{cos(x)cos(x)  )}{sin(x)cos(x)}
    Combine the fractions, then use sin(x)=sin^2(x)/sin(x) and you can get the tan and the sin^2 from that

    god damnit why am I always late
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    (Original post by RDKGames)
    sinx/cosx + cosx/sinx = (sin^2x + cos^2x)/sinxcosx by making both fractions have a common denominator.

    The top =1 by identity.

    Now divide top and bottom by cosx, then multiply top and bottom by sinx
    I got 1/cosxsinx but I didn't think it was relevant to the question xD
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    (Original post by RDKGames)
    sinx/cosx + cosx/sinx = (sin^2x + cos^2x)/sinxcosx by making both fractions have a common denominator.

    The top =1 by identity.

    Now divide top and bottom by cosx, then multiply top and bottom by sinx
    That gives me sinx/sinxcos^2x what do I do now?
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    (Original post by mariejuana)
    That gives me sinx/sinxcos^2x what do I do now?
    From what I said, it should be (sinx/cosx)/sin^2x
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    (Original post by RDKGames)
    From what I said, it should be (sinx/cosx)/sin^2x
    When you say "top and bottom" do you mean the expression or to the numerator and the denominator
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    (Original post by mariejuana)
    When you say "top and bottom" do you mean the expression or to the numerator and the denominator
    By top and bottom I am referring to the numerator and denominator
 
 
 

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