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If 2^x = 8, then x equals
A1
B2
C4
D3
Answer & Solution
Correct answer: D. 3
1. Express 8 as a power of 2: 8 = 2^3.
2. Equation becomes 2^x = 2^3.
3. Equal bases imply equal exponents: x = 3.
4. The answer is 3.
_Source: ICAI BoS Foundation Paper 3, Ch 1 Unit III 'Indices', p.13_
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