Exponential functions have the unknown in the exponent (power).

Exponential graphs have an asymptote at (x=0) and a (y)-intercept of (1).

(y=a^x, a > 1 )

mtaimg/images/topics/6/6-62-1.png/mtaimg

(y=a^x, 0 < a < 1 )

mtaimg/images/topics/6/6-62-2.png/mtaimg

Exponential functions where (a<0) are beyond the scope of A-Level Maths.

[b]uThe natural base[/u]/b

There is a special case when (a = e).

(e) is known as the bnatural base/b and is equal to (2.71828182846...) It is an irrational constant (similar to (\pi)).

(y=e^x )

mtaimg/images/topics/6/6-62-3.png/mtaimg