If a sum of money is deposited in a savings account that is paying x percent annual interest (expressed as a decimal), then this sum of money increased by a factor of (1+x)^3 after 3 years.

A. multiply this expression
B. Evaluate the polynomial expression found in part (A) for an annual interest rate of 10% or x=0.1.

multiply the expression:
(1+x)^3

kind of pointless in this context, but

(1+x)^3 = 1 + 3x + 3x^2 + x^3

(1 + .1)^3 = 1.1^3 = 1.331

Technically, the problem is worded wrong. If the rate is x% annually, then the expression is (1 + x/100).

To multiply the expression (1+x)^3, we can use the exponentiation rule that states: (a^m)^n = a^(m*n).

In this case, we have (1+x)^3, which means (1+x) raised to the power of 3. Applying the exponentiation rule, we get:

(1+x)^3 = 1^3 * x^3

Since any number raised to the power of 1 is itself, we can simplify the expression further:

(1+x)^3 = x^3

So, the expression (1+x)^3 simplifies to x^3.

Now, let's move to the next part of the question:

Evaluate the polynomial expression found in part (A) for an annual interest rate of 10% or x=0.1.

To evaluate the polynomial expression x^3 for x=0.1, we substitute the value of x into the expression:

x^3 = (0.1)^3

To calculate this, we raise 0.1 to the power of 3:

(0.1)^3 = 0.001

Therefore, when the annual interest rate (x) is 10% or 0.1, the expression (1+x)^3 evaluates to 0.001.