1. **Problem:** Solve the equation $$\left(\frac{16}{18}\right)^{x-1} = \left(\frac{6}{9}\right)^{\frac{x}{2}}$$.
2. **Step 1: Simplify the bases.**
$$\frac{16}{18} = \frac{8}{9} \quad \text{and} \quad \frac{6}{9} = \frac{2}{3}$$
3. **Step 2: Express bases as powers of prime factors.**
$$\frac{8}{9} = \frac{2^3}{3^2}$$
$$\frac{2}{3} = \frac{2^1}{3^1}$$
4. **Step 3: Rewrite the equation using these bases:**
$$\left(\frac{2^3}{3^2}\right)^{x-1} = \left(\frac{2}{3}\right)^{\frac{x}{2}}$$
5. **Step 4: Apply power of a quotient rule:**
$$\frac{2^{3(x-1)}}{3^{2(x-1)}} = \frac{2^{\frac{x}{2}}}{3^{\frac{x}{2}}}$$
6. **Step 5: Equate the powers of 2 and 3 separately:**
Since the bases are the same on both sides, the exponents must be equal:
$$3(x-1) = \frac{x}{2} \quad \text{and} \quad 2(x-1) = \frac{x}{2}$$
7. **Step 6: Solve the first equation:**
$$3x - 3 = \frac{x}{2}$$
Multiply both sides by 2:
$$2(3x - 3) = x$$
$$6x - 6 = x$$
Subtract $x$ from both sides:
$$6x - x = 6$$
$$5x = 6$$
$$x = \frac{6}{5} = 1.2$$
8. **Step 7: Solve the second equation:**
$$2x - 2 = \frac{x}{2}$$
Multiply both sides by 2:
$$4x - 4 = x$$
Subtract $x$ from both sides:
$$4x - x = 4$$
$$3x = 4$$
$$x = \frac{4}{3} \approx 1.333$$
9. **Step 8: Check for consistency.**
The two values for $x$ differ, so the only way for the original equation to hold is if both sides are equal for the same $x$. Since the bases are not equal, the equation holds only if the exponents satisfy both conditions simultaneously.
10. **Step 9: Re-express the original equation using logarithms to find $x$:**
Take natural logarithm on both sides:
$$\ln\left(\left(\frac{8}{9}\right)^{x-1}\right) = \ln\left(\left(\frac{2}{3}\right)^{\frac{x}{2}}\right)$$
$$ (x-1) \ln\left(\frac{8}{9}\right) = \frac{x}{2} \ln\left(\frac{2}{3}\right)$$
11. **Step 10: Solve for $x$:**
$$x \ln\left(\frac{8}{9}\right) - \ln\left(\frac{8}{9}\right) = \frac{x}{2} \ln\left(\frac{2}{3}\right)$$
Bring all $x$ terms to one side:
$$x \ln\left(\frac{8}{9}\right) - \frac{x}{2} \ln\left(\frac{2}{3}\right) = \ln\left(\frac{8}{9}\right)$$
Factor $x$:
$$x \left(\ln\left(\frac{8}{9}\right) - \frac{1}{2} \ln\left(\frac{2}{3}\right)\right) = \ln\left(\frac{8}{9}\right)$$
12. **Step 11: Calculate the logarithms (approximate):**
$$\ln\left(\frac{8}{9}\right) \approx \ln(0.8889) \approx -0.1178$$
$$\ln\left(\frac{2}{3}\right) \approx \ln(0.6667) \approx -0.4055$$
13. **Step 12: Substitute values:**
$$x \left(-0.1178 - \frac{1}{2}(-0.4055)\right) = -0.1178$$
$$x \left(-0.1178 + 0.20275\right) = -0.1178$$
$$x (0.08495) = -0.1178$$
14. **Step 13: Solve for $x$:**
$$x = \frac{-0.1178}{0.08495} \approx -1.386$$
**Final answer:**
$$\boxed{x \approx -1.386}$$
Solve Exponential C69401
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