Hard Logarithm Problems With Solutions Pdf Official

Expand: (a\ln 2 + 2(\ln 2)^2 = a^2 + a\ln 2).

Test simple integer (x=2): LHS = (\log_2(7) + \log_3(4) \approx 2.807 + 1.261 = 4.068 > 2) — not working, maybe no simple? Try (x=3): (\log_3(9)=2), (\log_4(5)\approx 1.16), sum=3.16>2. (x) large → each term ~1, sum ~2. Try (x=5): (\log_5(13)\approx 1.593), (\log_6(7)\approx 1.086), sum=2.679. Not 2.

Answer: No real solution. Domain: (x>0, x\neq 1, 2x>0, 2x\neq 1, 4x>0, 4x\neq 1) → (x>0, x\neq 1, x\neq 0.5, x\neq 0.25).

Challenging Exercises for Advanced High School & Early College Students hard logarithm problems with solutions pdf

Equation: (\frac{\ln(2x+3)}{\ln x} + \frac{\ln(x+2)}{\ln(x+1)} = 2).

Cancel (\ln 2) (non‑zero): [ \frac{\ln 2}{\ln x \cdot \ln(2x)} = \frac{1}{\ln(4x)} ] Cross‑multiply: (\ln 2 \cdot \ln(4x) = \ln x \cdot \ln(2x)).

Use (\log A + \log B = \log(AB)): [ \log_5 \left[ (x^2 - 4x + 5)(x^2 + 4x + 5) \right] = 2 ] But ((a-b)(a+b) = a^2 - b^2): Let (a=x^2+5), (b=4x): [ (x^2+5 - 4x)(x^2+5+4x) = (x^2+5)^2 - (4x)^2 = x^4 + 10x^2 + 25 - 16x^2 ] [ = x^4 - 6x^2 + 25 ] So: [ \log_5 (x^4 - 6x^2 + 25) = 2 ] [ x^4 - 6x^2 + 25 = 5^2 = 25 ] [ x^4 - 6x^2 = 0 \quad \Rightarrow \quad x^2(x^2 - 6) = 0 ] (x=0) or (x=\pm\sqrt{6}). Expand: (a\ln 2 + 2(\ln 2)^2 = a^2 + a\ln 2)

Convert to base 10 (or natural log): Let (\ln x = t). (\log_2 x = \frac{t}{\ln 2}), (\log_3 x = \frac{t}{\ln 3}), (\log_4 x = \frac{t}{\ln 4} = \frac{t}{2\ln 2}).

Equation: (\frac{\ln 2}{\ln x} \cdot \frac{\ln 2}{\ln(2x)} = \frac{\ln 2}{\ln(4x)}).

Change base: (\log_{x}(2x+3) = \frac{\ln(2x+3)}{\ln x}), (\log_{x+1}(x+2) = \frac{\ln(x+2)}{\ln(x+1)}). (x) large → each term ~1, sum ~2

Title: Hard Logarithm Problems with Detailed Solutions

Check domain: both >0, ≠1, ≠0.5, ≠0.25? (2^{\sqrt{2}} \approx 2^{1.414}\approx 2.665) fine. (2^{-\sqrt{2}} \approx 0.375) — not 0.5 or 0.25, fine.