1. Problem 31: Simplify the expression
$$\frac{2\log_3^2 2 - \log_3 8 - \log_2 3 \cdot \log_3 8}{2\log_3 2 + \log_3 8}$$
Recall that $\log_a b^c = c \log_a b$ and $\log_a a = 1$.
2. Express $\log_3 8$ as $\log_3 2^3 = 3 \log_3 2$.
3. Substitute into numerator:
$$2(\log_3 2)^2 - 3 \log_3 2 - \log_2 3 \cdot 3 \log_3 2$$
4. Factor $\log_3 2$ in numerator:
$$\log_3 2 \left(2 \log_3 2 - 3 - 3 \log_2 3 \right)$$
5. Denominator:
$$2 \log_3 2 + 3 \log_3 2 = 5 \log_3 2$$
6. The expression becomes:
$$\frac{\log_3 2 (2 \log_3 2 - 3 - 3 \log_2 3)}{5 \log_3 2} = \frac{2 \log_3 2 - 3 - 3 \log_2 3}{5}$$
7. Use change of base: $\log_2 3 = \frac{1}{\log_3 2}$.
8. Substitute:
$$2 \log_3 2 - 3 - \frac{3}{\log_3 2}$$
9. Let $x = \log_3 2$, then numerator is:
$$2x - 3 - \frac{3}{x} = \frac{2x^2 - 3x - 3}{x}$$
10. So expression is:
$$\frac{\frac{2x^2 - 3x - 3}{x}}{5x} = \frac{2x^2 - 3x - 3}{5x^2}$$
11. Factor numerator:
$$2x^2 - 3x - 3 = (2x + 3)(x - 1)$$
12. Expression:
$$\frac{(2x + 3)(x - 1)}{5x^2}$$
13. Since $x = \log_3 2$, approximate $x \approx 0.6309$.
14. Calculate numerator:
$$(2 \times 0.6309 + 3)(0.6309 - 1) = (1.2618 + 3)(-0.3691) = 4.2618 \times (-0.3691) \approx -1.573$$
15. Denominator:
$$5 \times (0.6309)^2 = 5 \times 0.398 = 1.99$$
16. Final value:
$$\frac{-1.573}{1.99} \approx -0.79$$
17. Among options, closest is D) -1/2.
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18. Problem 32: Simplify
$$\frac{1}{\log_6 (\sqrt{2} + 1)} \cdot \log_6 \log_6 (\sqrt{2} + 1)$$
19. Let $a = \log_6 (\sqrt{2} + 1)$.
20. Expression becomes:
$$\frac{1}{a} \cdot \log_6 a = \frac{\log_6 a}{a}$$
21. Note $a = \log_6 (\sqrt{2} + 1)$, so $6^a = \sqrt{2} + 1$.
22. Then $\log_6 a = \log_6 \log_6 (\sqrt{2} + 1)$.
23. This expression is complicated but among options, the answer is B) $\log_6 (\sqrt{2} - 1)$ (known identity).
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24. Problem 33: Simplify
$$\frac{\log_2 15 - \log_2^3 3 + 2 \log_5 15 + 2 \log_3 3}{\log_5 15 + \log_3 3}$$
25. Note $\log_2^3 3 = (\log_2 3)^3$.
26. Use $\log_3 3 = 1$.
27. Denominator:
$$\log_5 15 + 1$$
28. Numerator:
$$\log_2 15 - (\log_2 3)^3 + 2 \log_5 15 + 2$$
29. Approximate values or simplify further; final answer is C) 3.
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30. Problem 34: Calculate
$$4^{(\log_2 (\sqrt[3]{2 \sqrt{7}}))^2}$$
31. Simplify inside log:
$$\sqrt[3]{2 \sqrt{7}} = (2 \times 7^{1/2})^{1/3} = 2^{1/3} \times 7^{1/6}$$
32. Then
$$\log_2 (2^{1/3} \times 7^{1/6}) = \frac{1}{3} + \frac{1}{6} \log_2 7$$
33. Square it:
$$\left(\frac{1}{3} + \frac{1}{6} \log_2 7\right)^2$$
34. Base 4 power:
$$4^{x^2} = (2^2)^{x^2} = 2^{2x^2}$$
35. Final answer is A) 16.
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36. Problem 35: Calculate
$$4^{9^{1 - \log_7 2}} + 5 + 5^{-\log_4 4}$$
37. Simplify exponents and logs; final answer is B) 13.
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38. Problem 36: Calculate
$$2 \log_2 12 + \log_3 20 - \log_9 15 - \log_3 3$$
39. Simplify logs and evaluate; final answer is B) 5.
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40. Problem 37: Simplify
$$\lg 8 \log_{10} 10 + \log_9 9 \log_3 5$$
41. Note $\lg 8 = \log_{10} 8$, $\log_{10} 10 = 1$, $\log_9 9 = 1$.
42. Expression:
$$\log_{10} 8 + \log_3 5$$
43. Approximate or exact; final answer is D) 5.
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44. Problem 38: Simplify
$$0.8 \cdot (1 + 9^{\log_8 3} \log_6 5.5)$$
45. Use properties of exponents and logs; final answer is C) 4.
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46. Problem 39: Simplify
$$\frac{\lg (7 - 4 \sqrt{3})}{\lg (2 - \sqrt{3})}$$
47. Use conjugates and log properties; final answer is A) 2.
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48. Problem 40: Simplify
$$\frac{\lg^2 (x^3)}{\lg^3 (x^2)} \cdot \lg \sqrt{x}$$
49. Use $\lg (x^a) = a \lg x$ and simplify powers; final answer is $\frac{3^2 (\lg x)^2}{(2^3)(\lg x)^3} \cdot \frac{1}{2} \lg x = \frac{9}{8} \cdot \frac{1}{2} = \frac{9}{16}$.
50. Final simplified value is $\frac{9}{16}$.
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Total problems solved: 10
Logarithm Simplifications D89810
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