What is the coefficient of x^2 in the expansion of (1 + x)^6?
Answer and explanation
Correct answer: B. 15
- Step 1: The coefficient of x^2 is 6C2 = 6 x 5 / 2 = 15. Answer: 15. Why not the others: 6: That is the coefficient of x. 20: That is the coefficient of x^3. 30: That is 2 x 15.
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