Category
Trigonometry
Identities, transformations, and angles that refuse to simplify.
Trigonometry sits between algebra and geometry, and contest problems exploit both sides of it. Identities compress an ugly expression; the unit circle turns angle chasing into arithmetic.
You will find identity manipulation, equations over restricted domains, sums of trigonometric series, and problems where the trigonometric form is a disguise for something much simpler underneath.
Latest problems
37 problems
Counting Trig Solutions
667
2
Period of a Sum of Cosine Functions
1488
18
Probability That a Sine Value Is Rational
1147
24
sin 80 is a root
1548
16
Maximizing Area of a Trigonometric Rectangle
1195
15
Rewriting a Sinusoidal Expression
1250
10
A Dodecagon's Total Reach
1583
11
A Heptagon's Hidden Product
1667
14
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