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正弦型函数
三种标准变换（竖直平移、水平平移与竖直伸缩）如何影响正弦曲线与余弦曲线的中线、振幅、值域与周期？
1. Introduction
Introduction
2. Shifts and vertical stretches of the sine and cosine functions
Shifts and vertical stretches of the sine and cosine functions
3. Horizontal scaling
Horizontal scaling
4. Circular functions with different periods
Circular functions with different periods
5. Summary
Summary
6. Vertical scaling of cosine
How do g(t) = 3 cos(t) and h(t) = (1/4) cos(t) differ from f = cos(t)?
7. Horizontal scaling of a sinusoid
How do h(t) = f(t/3) and j(t) = f(4t) relate to f(t) = cos(t)?
8. Reading parameters from a formula
For p(x) = sin(10x) + 2, what are the period, amplitude, midline and range?
9. Parameters with a horizontal shift
For w(x) = 2 cos((pi/2)(x - 3)) + 5, what are the period and horizontal shift?
10. Fitting a formula from a table
A table of values repeats every 1.0 unit, ranges between 1 and 3, and starts at 2 when x = 0. Which formula fits?
11. Period of a scaled sine
For u(x) = -0.25 sin(3x - 6) + 5, what is the period? Give the exact value as a multiple of pi, numerator over denominator.
12. Sine and cosine differ only by a shift
The graph of cos(t) is the graph of sin(t) shifted horizontally by pi/2.