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2×4×8×16(log⁡24)2(log⁡48)3(log⁡816)4\small \dfrac{2\times4\times8\times16}{(\log_2 4)^2 (\log_4 8)^3 (\log_8 16)^4} is equal to

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Solution

✅ Correct Answer: 24

2×4×8×16=10242 \times 4 \times 8 \times 16 = 1024


For logarithms like these, we'll use the logarithm property: log⁡abn=nlog⁡ab\log_a b^n = n \log_a b

Also, when the base and argument are both powers of the same number, we can use: log⁡ambn=nmlog⁡ab\log_{a^m} b^n = \tfrac{n}{m} \log_a b

Let's calculate each logarithm:

Finding log⁡24\log_2 4:

log⁡24=log⁡222=2\log_2 4 = \log_2 2^2 = 2

Finding log⁡48\log_4 8:

Since 4=224 = 2^2 and 8=238 = 2^3:

log⁡48=log⁡2223=32\log_4 8 = \log_{2^2} 2^3 = \tfrac{3}{2}

Finding log⁡816\log_8 16:

Since 8=238 = 2^3 and 16=2416 = 2^4:

log⁡816=log⁡2324=43\log_8 16 = \log_{2^3} 2^4 = \tfrac{4}{3}


(log⁡24)2(log⁡48)3(log⁡816)4(\log_2 4)^2 (\log_4 8)^3 (\log_8 16)^4

=(2)2×(32)3×(43)4= (2)^2 \times \left(\tfrac{3}{2}\right)^3 \times \left(\tfrac{4}{3}\right)^4

=4×278×25681= 4 \times \tfrac{27}{8} \times \tfrac{256}{81}

4×278=1088=2724 \times \tfrac{27}{8} = \tfrac{108}{8} = \tfrac{27}{2}

272×25681=27×2562×81=6912162\tfrac{27}{2} \times \tfrac{256}{81} = \tfrac{27 \times 256}{2 \times 81} = \tfrac{6912}{162}

6912162=1283\tfrac{6912}{162} = \tfrac{128}{3}


NumeratorDenominator=10241283=1024×3128=3072128=24\tfrac{\text{Numerator}}{\text{Denominator}} = \tfrac{1024}{\tfrac{128}{3}} = \tfrac{1024 \times 3}{128} = \tfrac{3072}{128} = 24

Answer: 24


When you see logarithms with bases and arguments that are powers of the same number, use the property log⁡ambn=nmlog⁡ab\log_{a^m} b^n = \tfrac{n}{m} \log_a b

This makes complex logarithmic expressions much simpler to handle

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