Transformations
Reflecting Across the y-axis
When the exponent is negative, the graph will be reflected across the y-axis. The table and graph below represent the function, y = 5 -x. Notice in the table, when the x-values are negative, the opposite value of x will be positive, so the graph will grow quickly on the left-hand side. On the other hand, when the x-values are positive, the opposite value of x will be negative, so the graph will stay very close to the x-axis.
This type of function is known as exponential decay. Any function with a negative exponent or a b-value between 0 and 1 will create a curve that decreases from left to right.