Question
Add: $4y(3y^2+ 5y – 7)$ and $2(y^3– 4y^2+ 5)$
✓
Answer
The first expression $= 4y(3y^2+ 5y – 7) = (4y \times 3y^2) + (4y \times 5y) + (4y \times (–7)) = 12y^3+ 20y^2– 28y$
The second expression $= 2(y^3– 4y^2+ 5) = 2y^3+ 2 \times (– 4y^2) + 2 \times 5 = 2y^3- 8y^2+ 10$
Adding the two expressions,
Thus, the sum is $14y^3+ 12y^2- 28y + 10$
The second expression $= 2(y^3– 4y^2+ 5) = 2y^3+ 2 \times (– 4y^2) + 2 \times 5 = 2y^3- 8y^2+ 10$
Adding the two expressions,
Thus, the sum is $14y^3+ 12y^2- 28y + 10$
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