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Math Help - formula

  1. #1
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    formula

    Hello friends, I know, and there is this formula for the sum of sines:

    sin(\alpha) + sin(\beta) = 2sin( \displaystyle\frac{\alpha + \beta}{2} ) cos( \displaystyle\frac{\alpha - \beta}{2} )

    and there is one for the sum of cosines,

    I wonder if there is a similar to this:

    tan(\alpha) + tan(\beta)

    greetings
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  2. #2
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    Quote Originally Posted by Dogod11 View Post
    Hello friends, I know, and there is this formula for the sum of sines:

    sin(\alpha) + sin(\beta) = 2sin( \displaystyle\frac{\alpha + \beta}{2} ) cos( \displaystyle\frac{\alpha - \beta}{2} )

    and there is one for the sum of cosines,

    I wonder if there is a similar to this:

    tan(\alpha) + tan(\beta)

    greetings

    \tan{\alpha} \pm \tan{\beta} = \frac{\sin(\alpha \pm \beta)}{\cos{\alpha}\cos{\beta}}
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  3. #3
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    thanks
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  4. #4
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    Quote Originally Posted by Dogod11 View Post
    Hello friends, I know, and there is this formula for the sum of sines:

    sin(\alpha) + sin(\beta) = 2sin( \displaystyle\frac{\alpha + \beta}{2} ) cos( \displaystyle\frac{\alpha - \beta}{2} )

    and there is one for the sum of cosines,

    I wonder if there is a similar to this:

    tan(\alpha) + tan(\beta)

    greetings
    HI

     <br />
\frac{\sin \alpha\cos \beta \pm \cos \alpha \sin \beta}{\cos \alpha\cos \beta}=\frac{\sin (\alpha\pm \beta)}{\cos \alpha\cos \beta}<br />
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