Advanced Math practice question

Answer: 3

(x + y)³ = x³ + 3x²y + 3xy² + y³. The coefficient of x²y is 3.

Common wrong answers

If you answered 1

1 forgets that the x²y term arises three ways.

If you answered 2

2 comes from treating the cube as a square.

If you answered 6

6 doubles the coefficient, or counts x²y and xy² together.

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