Question

A 2-column table has 5 rows. The first column is labeled x with entries negative 2, negative 1, 0, 1, 2. The second column is labeled f (x) with entries three-fourths, three-halves, 3, 6, 12. Which exponential function is represented by the values in the table?

Answer 1

f(x) = 3(2)^x

Explanation:

The Table is:

x f(x)

-2 3/4

-1 3/2

0 3

1 6

2 12

The exponential funtion has the next form:

f(x) = a(b)^x

At x = 0, f(x) = a. Then, a = 3

Isolating b from the equation:

f(x)/a = b^x

ln(f(x)/a) = x*ln(b)

[ln(f(x)/a)]/x = ln(b)

At x = 1, f(x) = 6. Then:

[ln(6/3)]/1 = ln(b)

ln(2) = ln(b)

2 = b

Therefore, the function is f(x) = 3(2)^x