1 Answer

Itamar Lavender · Answer 1 · 2023-11-07T16:45:26+0000

Solution

David simplified a polynomial

For the first step

Open the brackets

$\begin{gathered} (4-x^2)(3x+2)+(5x^3-4x^2-7) \\ =(12x+8-3x^3-2x^2)+(5x^3-4x^2-7) \end{gathered}$

The first step is correct.

For the second step

Collect like terms

$\begin{gathered} (12x+8-3x^3-2x^2)+(5x^3-4x^2-7) \\ =(-3x^3+5x^3)+(-2x^2-4x^2)+(12x)+(8-7) \end{gathered}$

The second step is correct

For the third step

Add up the like terms

$\begin{gathered} (-3x^3+5x^3)+(-2x^2-4x^2)+(12x)+(8-7) \\ =(2x^3)+(-6x^2)+(12x)+(1) \\ \text{Open the brackets} \\ =2x^3-6x^2+12x+1 \end{gathered}$

The third step is correct.

Hence, David did not make a mistake

Please log in or register to add a comment.