SOLUTION: Find the equation for an exponential function that passes through the pair of points given below. (Round all coefficients to 4 decimal places when necessary.) HINT [See Example 2.]

Algebra ->  Linear-equations -> SOLUTION: Find the equation for an exponential function that passes through the pair of points given below. (Round all coefficients to 4 decimal places when necessary.) HINT [See Example 2.]      Log On


   



Question 1164875: Find the equation for an exponential function that passes through the pair of points given below. (Round all coefficients to 4 decimal places when necessary.) HINT [See Example 2.]
Through (2, 18) and (4, 162)
f(x) =

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=ab^x
18=ab^2
162=ab^4
so b^2=18/a
and therefore b^4=324/a^2
162 = 324/a
a=2
if a=2 then 18=2b^2 and b^2=9 and b=3
check with a=4 and 162=2*81=162 checks
the equation is f(x)=2*3^x
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