(2+y)^3
1. Use Cube of Sum: (a+b)^3=a^3+3a^2b+3ab^2+b^2
(2+y)(2^2+2*2y+y^2)
2. Simplify 2^2 to 4
(2+y)(4+2*2+y^2)
3. Simplify 2*2y to 4y
(2+y)(4+4y+y^2)
4. Distribute sum groups
2(4+4y+y^2)+y(4+4y+y^2)
5. Distribute
8+8y+2y^2+y(4+4y+y^2)
6. Distribute
8+8y+2y^2+4y+4y^2+y^3
7. Collect like terms
8+(8y+4y)+(2y^2+4y^2)+y^3
8. Simplify
8+12+6y^2+y^3
9. Write it nicely
y^3+6y^2+12y+8
Your answer is the first one, have a nice day :D
