Question

Which set of coefficients of the terms in the expansion of the binomial (x+y)^3 is correct ?

Answer 1

The expansion of (x+y)^3 is x^3 +3x^2×y+3x×y^2+y^3 the coefficients are 1,3,3,1

Answer 2

We are technically FOILing this out... with a power of 3.

(x+y)(x+y)(x+y)

So we can first factor out the first two "x+y"s.

$( x^{2} +2xy + y^{2} )$, multiplied by the last "x+y".

$x^{3} +3 x^{2} y +3x y^{2} + y^{3}$

Coefficients are the number that comes in front of a variable. 

In this case, 1 comes in front of $x^{3}$, 3 comes in front of $x^{2} y$, 3 comes in front of $x y^{2}$, and 1 comes in front of $y^{3}$.

Thus: 1, 3, 3, 1.
         Answer Choice A