It's a 2nd degree algebraic expression in ' y '.
It's pretty messy in this form, and it can be substantially cleaned up.
Looking at just the second term, we can remove the parentheses:
3 (4y² - 2) = 12y² - 6
Now we can put that into the original expression ... 3y² + 12y² - 6
then combine the y² terms: 15y² - 6 .
If you want to go one step farther, we can factor it: 3(5y² - 2)