Answer: 30/99.
- A 30/100 = 3/10
- B 30/99
- C 30/100
- D 1/10
Correct answer: B. 30/99
Explanation: tan(x+y) = (tanx + tany)/(1 - tanx tany) = 33. (3+tany)/(1-3tany) = 33. 3+tany = 33-99tany. 100tany = 30. tany = 30/100 = 3/10. Wait that is same as option A. But 3/10 = 30/100. So both A and C say same thing differently.
Unit circle with standard angles 0, 30, 45, 60, 90 degrees; at 45 degrees the point is (cos45, sin45) = (1/sqrt2, 1/sqrt2).
Concept context
Ratios, identities, and applications in triangles