In the general form of an exponential growth function, \( f(x) = a \cdot b^x \):
- \( a \) represents the initial value.
- \( b \) represents the growth factor.
- For an exponential growth function with \( a > 0 \), \( b \) must be greater than 1.
So the complete answers are:
- \( a \) represents the initial value;
- \( b \) represents the growth factor;
- \( b \) must be greater than 1.