MathDB

1

Part of 2011 German National Olympiad

Problems(1)

Inequality involving Sine values

Source: Germany 2011, Grade 13 - #1

5/30/2016
Prove for each non-negative integer nn and real number xx the inequality sin⁡x⋅(nsin⁡x−sin⁡nx)≥0 \sin{x} \cdot(n \sin{x}-\sin{nx}) \geq 0
inequalitiestrigonometryalgebra unsolvedalgebrasine double angle