Concept:
If f is a function and c is a positive constant, then the graph of y=cf(x) is the graph of y=f(x)
- compressed (shrunk) vertically by a factor of c if c < 1 , or
- stretched vertically by a factor of c if c > 1.
Similarly, if f is a function and d is a positive constant, then the graph of y=f(dx) is the graph of y=f(x)
- stretched horizontally by a factor of 1/d if d < 1 , or
- compressed (shrunk) horizontally by a factor of 1/d if d > 1.
