Answer :
In the form f(x) = b^x, It is not necessary that b>0. b can be both greater than and less than 0. But it can't be 0 because then f(x) will be 0 which is not a exponential function.
Exponential function : [tex]f (x) = b^x [/tex]
Examples of some exponential functions are :
[tex]e^x, 2^x, 3^x, 10^x, e^{-x}, 10^{-x}, [/tex]
Generally they are studied like that. if b > 0, then b^x is > 0 and f(x) > 0.
b can be taken as negative also, where it is needed. But in general when we talk about exponentially increasing function it is e^x and when it is exponentially decreasing we use e^-x.
If b = 0, then f (x) = 0, so it does not increase or decrease.
Examples of some exponential functions are :
[tex]e^x, 2^x, 3^x, 10^x, e^{-x}, 10^{-x}, [/tex]
Generally they are studied like that. if b > 0, then b^x is > 0 and f(x) > 0.
b can be taken as negative also, where it is needed. But in general when we talk about exponentially increasing function it is e^x and when it is exponentially decreasing we use e^-x.
If b = 0, then f (x) = 0, so it does not increase or decrease.