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The value of log(1/64) base 4 is
A3
B-3
C-2
D-4
Answer & Solution
Correct answer: B. -3
1. 1/64 = 64^(-1) = (4^3)^(-1) = 4^(-3).
2. log base 4 of 4^(-3) = -3 by the definition log_b(b^x) = x.
3. So log_4(1/64) = -3.
4. Option C uses the wrong base power and is incorrect.
_Source: ICAI BoS Foundation Paper 3, Ch 1 Unit IV 'Logarithms', p.16_
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