f(x) = a · sin(b · (x + c)) + d
Change amplitude, midline, period and shift of the sine curve, read the shift inside the bracket correctly and use the model for a tide.
- France: grade 11
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- Syria: grade 10
- Palestine: grade 10
- Ukraine: grade 10
Guide
The curve of f(x) = a·sin(b·(x + c)) + d is the sine curve stretched and shifted. The x-axis counts in radians, so one full wave of sin x ends at 2π.
|a| is the amplitude, the line y = d is the midline. The curve oscillates between d − |a| and d + |a|.
The period is p = 2π/b: a bigger b squeezes the wave. The term x + c inside the bracket shifts the graph by c to the LEFT (for c > 0).
Set the calculator to radians (RAD) when you evaluate sin with an argument like π/6 · t.