Step-by-step explanation:
Hey there!
Given;
[tex] = ( - 4 {b}^{2} + 8b) + ( - 4 {b}^{3} + 5 {b}^{2} - 8b)[/tex]
Open brackets.
[tex] = - 4 {b}^{2} + 8b - 4 {b}^{3} + 5 {b}^{2} - 8b[/tex]
Simplify the like terms.
[tex] = - 4 {b}^{3} - 4 {b}^{2} + 5 {b}^{2} + 8b - 8b[/tex]
"+8b" and "-8b" cancelled. And "-4b^2" and "+5b^2" will be subtracted.
[tex] = - 4 {b}^{3} + {b}^{2} [/tex]
Therefore the required answer is -4b^3+b^2.
Hope it helps...
