We are given the equation $\frac{4x^3}{a} = 1$ and asked to find the value of $a$.

1. Problem Description

We are given the equation $\frac{4x^3}{a} = 1$ and asked to find the value of $a$.

2. Solution Steps

We need to isolate $a$ in the given equation.

$\frac{4x^3}{a} = 1$

Multiply both sides by $a$:

$4x^3 = a$

Thus, $a = 4x^3$.

3. Final Answer

The value of $a$ is $4x^3$.