Find the coefficient of y^4 in the expansion of (2y-5+3y^2)^6.
Here's the entire expansion (I have no life)
729y12+2916y11−2430y10−19980y9+135y8+59976y7+6364y6−99960y5+375y4+92500y3−18750y2−37500y+15625
The answer is 375
Thanks! :)