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Evaluate the expression. 50 points!!

Evaluate the expression. 50 points!!-example-1
User Angle
by
5.8k points

2 Answers

5 votes

Answer:

c

Explanation:

User Brendan Kowitz
by
5.6k points
2 votes

Answer:

C

Explanation:

If you notice, this is what the tangent-difference identity resembles. The tangent-difference identity is:


\tan(\alpha-\beta)=(\tan(\alpha)-\tan(\beta))/(1-\tan(\alpha)\tan(\beta))

We have the expression:


(\tan((\pi)/(7))-\tan((\pi)/(8)))/(1-\tan((\pi)/(7))\tan((\pi)/(8)))

So, our α is π/7 and our β is π/8. Therefore:


(\tan((\pi)/(7))-\tan((\pi)/(8)))/(1-\tan((\pi)/(7))\tan((\pi)/(8)))=\tan((\pi)/(7)-(\pi)/(8)})

Simplify:


(\tan((\pi)/(7))-\tan((\pi)/(8)))/(1-\tan((\pi)/(7))\tan((\pi)/(8)))=\tan((8\pi)/(56)-(7\pi)/(56)})

Subtract:


(\tan((\pi)/(7))-\tan((\pi)/(8)))/(1-\tan((\pi)/(7))\tan((\pi)/(8)))=\tan((\pi)/(56))

So, our answer is C.

And we're done!

User Torial
by
5.2k points