00:01
So we're given a graph and we want to write the exponential function that's going to describe this graph.
00:06
And we can see it's a decay and we can see that there's a point at zero and three.
00:11
And then the graph decays along and we're given another point at the point four and 1 .49.
00:20
And we want to figure out the model.
00:22
So we know it's in the form of y equals a, b to the x.
00:26
We also know that our little a, b, or...
00:31
Value is going to be three so we know the equation is this much and the only thing we need to find is what this b value is but we know a point so we can plug it in when y is 1 .49 x is 4 and so we divide both sides by 3 and then we can either take the fourth root or take each side to the one -fourth power which is the same thing as fourth rooting and i will take it to the 1 4th power.
01:07
And we don't have to worry about plus or minus, because that isn't even root.
01:11
And usually even roots, we would put plus or minus...