How to Use Phase Shift Calculator
The Phase Shift Calculator extracts the horizontal shift, period, amplitude, and vertical displacement from a trigonometric function definition. Choose the function type (sine or cosine), select the input form, fill in the parameters, and the calculator shows all transformation values instantly.
- Choose the function — Select sin or cos.
- Choose the input form — Standard form (A·f(Bx − C) + D) or factored form (A·f(B(x − h)) + D).
- Enter the parameters — Fill in A, B, C (or h), and D.
- Review the results — The Phase Shift Calculator shows the phase shift, its direction (left or right), period, amplitude, and vertical shift.
If B = 0, the function is constant and the phase shift is undefined. The calculator will prompt you to enter a non-zero value for B.
Formula & Theory - Phase Shift Calculator
The Phase Shift Calculator uses this core formula or rule: standard trigonometric transformation formulas:
Standard form: y = A · sin(Bx − C) + D
Phase Shift = C / B
Period = 2π / |B|
Amplitude = |A|
Factored form: y = A · sin(B(x − h)) + D
Phase Shift = h
(Equivalent: C = B·h)
| Symbol | Meaning |
|---|---|
| A | Amplitude (height from midline to peak) |
| B | Frequency factor (affects period) |
| C | Phase constant in standard form |
| h | Horizontal shift in factored form |
| D | Vertical shift (midline) |
The sign of the phase shift determines the direction: if C/B > 0, the graph moves right by C/B units; if C/B < 0, it moves left by |C/B| units. This is because the zero-crossing or peak of the function moves in the positive x direction when C is positive.
Assumptions and Limits
B must be non-zero. The amplitude is always taken as a positive value |A|; a negative A reflects the graph vertically. This calculator handles real-number inputs only.
Use Cases for Phase Shift Calculator
The Phase Shift Calculator is particularly useful in:
- Trigonometry courses — Identify all four transformation parameters from a function equation quickly.
- Graphing functions — Determine exactly where the first peak, trough, and zero occur on a shifted graph.
- Physics and engineering — Analyze phase differences between waves in AC circuits, sound waves, or oscillations.
- Homework and exam preparation — Verify the phase shift calculation before sketching the graph.
- Comparing two functions — Assess the phase difference between y = sin(2x − π) and y = sin(2x + π/2).
The Phase Shift Calculator eliminates the arithmetic step of dividing C by B and clearly labels the shift direction, which is a common source of sign errors in student work.