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simplify each expression. tan (pi/9)+ tan (8pi/9) / (1-tan pi/9 times tan 8pi/9)

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user1552382 | eNotes Newbie

Posted February 24, 2013 at 10:10 PM via web

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simplify each expression. tan (pi/9)+ tan (8pi/9) / (1-tan pi/9 times tan 8pi/9)

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embizze | High School Teacher | (Level 1) Educator Emeritus

Posted February 24, 2013 at 11:22 PM (Answer #1)

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Simplify `(tan(pi/9)+tan((8pi)/9))/(1-tan(pi/9)tan((8pi)/9))` :

We use the identity `tan(A+B)=(tanA+tanB)/(1-tanAtanB)`

`tan(pi/9+(8pi)/9)=tanpi=0`

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The simplified form is 0

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