1. **State the problem:** Find the non-zero values of $a$ and $b$ such that $$(2x - a)^3 = 8x^3 - bx^2 + 2bx - a^3.$$
2. **Recall the binomial expansion formula:** For any $u$ and $v$, $$(u - v)^3 = u^3 - 3u^2v + 3uv^2 - v^3.$$
3. **Apply the formula to the left side:** Let $u = 2x$ and $v = a$, then
$$ (2x - a)^3 = (2x)^3 - 3(2x)^2 a + 3(2x) a^2 - a^3 = 8x^3 - 12x^2 a + 6x a^2 - a^3.$$
4. **Set the expanded left side equal to the right side:**
$$8x^3 - 12x^2 a + 6x a^2 - a^3 = 8x^3 - b x^2 + 2b x - a^3.$$
5. **Cancel $8x^3$ and $-a^3$ from both sides:**
$$\cancel{8x^3} - 12x^2 a + 6x a^2 - \cancel{a^3} = \cancel{8x^3} - b x^2 + 2b x - \cancel{a^3}.$$
6. **Simplify the equation:**
$$-12x^2 a + 6x a^2 = -b x^2 + 2b x.$$
7. **Group terms by powers of $x$:**
$$(-12 a + b) x^2 + (6 a^2 - 2 b) x = 0.$$
8. **For this to hold for all $x$, coefficients of $x^2$ and $x$ must be zero:**
$$\begin{cases} -12 a + b = 0 \\ 6 a^2 - 2 b = 0 \end{cases}$$
9. **Solve the system:**
From the first equation:
$$b = 12 a.$$
Substitute into the second:
$$6 a^2 - 2 (12 a) = 0 \implies 6 a^2 - 24 a = 0.$$
10. **Factor the second equation:**
$$6 a (a - 4) = 0.$$
Since $a \neq 0$,
$$a - 4 = 0 \implies a = 4.$$
11. **Find $b$ using $b = 12 a$:**
$$b = 12 \times 4 = 48.$$
**Final answer:**
$$a = 4, \quad b = 48.$$
Find A B 666078
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