Question

The graph below could be the graph of which exponential function?

A. F(x) = 3 • (1.2)^x
B. F(x) = 3 • (0.2)^x
C. F(x) = 3^x
D. F(x) = 3 • (-1.2)^x

Answer 1

A. Now you could just use desmos and get the graph. But to explain it quickly, find points
First we know it cannot be 3*(-1.2)^x because it would be heading down not up. Then solve for x=0
We know for c 3^0 = 1 so (0,1) but that’s clearly not on the graph in fact the x int is 3 (0,3) so it must be A or B.
Now solve another easy point, where X = 1
Cause that’s just itself , so apply it to A and B
A: (1,3.6)
B: (1,0.6)
And clearly the graph increases in y as x increases. So it must be A.
See graph below: