Chapter 7, Problem 14CT

To determine

To find: the function $y=3\cdot 5^x$ values at -1, 2 and 3.

Answer to Problem 14CT

The values of functions at -1, 2 and 3 are $\frac{3}{5}$ , 75 and 375 respectively.

Explanation of Solution

Given:

The function is $y=3\cdot 5^x$ .

Calculation:

Solve the function as follows:

For x = -1,

  $\begin{array}{c}y=3\cdot 5^{-1}\\ =3\cdot \frac{1}{5}\\ =\frac{3}{5}\end{array}$

For x = 2,

  $\begin{array}{c}y=3\cdot 5^2\\ =3\cdot 25\\ =75\end{array}$

For x = 3,

  $\begin{array}{c}y=3\cdot 5^3\\ =3\cdot 125\\ =375\end{array}$

Thus, the values of functions at -1, 2 and 3 are $\frac{3}{5}$ , 75 and 375 respectively.