fully expand and simplify:
(3y^9 + 5) (-5y^7 + 8)
To fully expand and simplify the expression (3y^9 + 5)(-5y^7 + 8), we need to distribute each term in the first expression (3y^9 + 5) to each term in the second expression (-5y^7 + 8). This results in:
3y^9(-5y^7) + 3y^9(8) + 5(-5y^7) + 5(8)
Now, we simplify each term:
-15y^16 + 24y^9 - 25y^7 + 40
Therefore, the fully expanded and simplified expression is -15y^16 + 24y^9 - 25y^7 + 40.