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Trigonometry2D

Trigonometric Equations - Theory & Concepts - Trigonometry Periodic Solutions

Methods for solving linear, quadratic, and multiple-angle trigonometric equations.

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Periodic Solutions Explorer

Solve sin(x)=c\sin(x) = c and see how periodic solutions map onto the coordinate wave and the unit circle.

Value (cc)0.50
-1.00.01.0

Solutions in [2π,2π][-2\pi, 2\pi]

x1x_{1}:
-5.7596 rad~ -1.83π
x2x_{2}:
-3.6652 rad~ -1.17π
x3x_{3}:
0.5236 rad~ 0.17π
x4x_{4}:
2.6180 rad~ 0.83π
Trigonometric functions are periodic. The equation sin(x)=c\sin(x) = c has general solutions x=arcsin(c)+2nπx = \arcsin(c) + 2n\pi and x=πarcsin(c)+2nπx = \pi - \arcsin(c) + 2n\pi where nZn \in \mathbb{Z}.

Coordinate Wave: y = sin(x)

Periodic wave solutions plotHorizontal AxisVertical Axis-2π-1.5π-1π-0.5π0.5π1.5πTrigonometric WaveHorizontal Solution line y = cIntersection solution pointIntersection solution pointIntersection solution pointIntersection solution point

Unit Circle Projection

For sin(x)=c\sin(x) = c, the horizontal line at height y=cy = c intersects the circle at the solution angles.

Periodic solution mapping on unit circleUnit Circle BoundaryProjection line y = cSolution terminal rayTerminal pointSolution terminal rayTerminal pointOrigin