# calculus

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Find the exact value of the given expression.
(tan17pi/12 - tan pi/4) / (1+tan 17pi/12 tan pi/4)

can you help with this? i got the answer 1/ squareroot 3

• calculus -

I assume you used:

tan(A - B) = (tanA - tanB)/( 1 + tanAtanB)

then (tan17pi/12 - tan pi/4) / (1+tan 17pi/12 tan pi/4)
= tan(17π/12 - π/4)
= tan( 7π/6) or tan 210° ---> quad III
= 1/√3

• calculus -

You are correct!

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