Final answer:
To find the values of A and B in the exponential function f(t) = A*e^(B*t) that go through the points (0,5) and (9,4), substitute the points into the equation and solve for A and B. A = 5, B = ln(4/5)/9.
Step-by-step explanation:
To find the values of A and B in the exponential function f(t) = A*e^(B*t) that go through the points (0,5) and (9,4), we can substitute these points into the equation and solve for A and B.
Let's start with the point (0,5).
Substituting t=0 and f(t)=5 into the equation, we get:
5 = A*e^(B*0)
5 = A*1
So, A = 5.
Next, let's use the point (9,4).
Substituting t=9 and f(t)=4 into the equation, we get:
4 = 5*e^(B*9)
Dividing both sides by 5, we get:
4/5 = e^(B*9)
Taking the natural logarithm (ln) of both sides, we get:
ln(4/5) = B*9
Dividing both sides by 9, we get:
B = ln(4/5)/9.
Therefore, the values of A and B are A = 5 and B = ln(4/5)/9.