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1984 AMC 12 Question 23

AMC12 · 1984 AMC 12

Question 23

$\frac{\sin10^\circ+\sin20^\circ}{\cos10^\circ+\cos20^\circ}$ equals
  1. $\tan10^\circ+\tan20^\circ$
  2. $\tan30^\circ$
  3. $\frac12(\tan10^\circ+\tan20^\circ)$
  4. $\tan15^\circ$
  5. $\frac14\tan60^\circ$