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If A denotes the sum of all, the coefficients in the expansion of (1 – 3x + 10x 2 ) n and B denotes the sum of all the coefficients in the expansion of (1 + x 2 ) n , then:

1. 3A = B
2. B = A 3
3. A = 3B
4. A = B 3

Correct answer: A = B 3

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