Find `(x+a)^(3)-(x-a)^(3)`. Hence evaluate `(sqrt(5)+sqrt(4))^(3)-(sqrt(5)-sqrt(4))^(3)`

Explanation

To solve the problem, we need to find the expression \((x + a)^3 - (x - a)^3\) and then evaluate \((\sqrt{5} + \sqrt{4})^3 - (\sqrt{5} - \sqrt{4})^3\).

### Step 1: Expand \((x + a)^3\) and \((x - a)^3\)

Using the binomial theorem, we can expand both expressions:

\[
(x + a)^3 = x^3 + 3x^2a + 3xa^2 + a^3
...