Stage 25 · Trigonometry

25.6.4 Finding the Equation from the Graph

25.6 y=Asin(ωx+φ) and Simple Harmonic Motion

Point 4 of 5

25.6.4 Finding the Equation from the Graph

Core idea

Read a known wave in reverse — measure its height, its tightness, and its starting point — and you can work back to A, ω, and φ.

Module goal. We treat a sine wave's amplitude, period, and phase as adjustable dials, understand how each parameter reshapes the graph, and use it to describe real back-and-forth motions like springs and sound.
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