How would you expand (x + y)^4 ? (will become a fan&& give medal!)

Question

zepdrix · Answer

When expanding $\Large\rm (x+y)^n$
You'll always end up with $\Large\rm n+1$ terms.

So since we have a 4th degree binomial, we'll end up with 5 terms.
Each term will consist of `a coefficient` (we'll get back to that later),
and powers on x and y.

The power starts at 4 on x, and counts down.
it starts at 0 on y and counts up.$$\Large\rm (x + y)^4=\text{_}x^4y^0+\text{_}x^3y^1+\text{_}x^2y^2+\text{_}x^1y^3+\text{_}x^0y^4$$

zepdrix · Answer

See how the x's are counting down?
I left a little space in front of each term so we can fill in the coefficients.

zepdrix · Answer

To get the correct coefficients, turn to Pascal's Triangle.|dw:1400543897464:dw|