In the function y=0.9sin(1.1x-3.5)+8.5, what does the 1.1 do?
The value 1.1 in the function y=0.9sin(1.1x-3.5)+8.5 affects the frequency of the sine function. Specifically, it determines how many oscillations (complete cycles) occur in a given interval of x-values.
In this case, since the coefficient of x is inside the sine function, the value of 1.1 scales the x-axis. It stretches or compresses the graph horizontally. A larger value of 1.1 will result in a higher frequency, meaning that more oscillations occur in a given interval, while a smaller value of 1.1 will produce a lower frequency with fewer oscillations.