Solve {l}{a^2+b+2a-2a^2+2ab}{+4a+3a+3ab}

$$\left. \begin{array} { l } { a ^ { 2 } + b + 2 a - 2 a ^ { 2 } + 2 a b } \\ { + 4 a + 3 a + 3 a b } \end{array} \right.$$

Evaluate

$$b+9a+5ab-a^{2}$$

Solution Steps

Combine a^{2} and -2a^{2} to get -a^{2}.

$$-a^{2}+b+2a+2ab+4a+3a+3ab$$

Combine 2a and 4a to get 6a.

$$-a^{2}+b+6a+2ab+3a+3ab$$

Combine 6a and 3a to get 9a.

$$-a^{2}+b+9a+2ab+3ab$$

Combine 2ab and 3ab to get 5ab.

$$-a^{2}+b+9a+5ab$$

Differentiate w.r.t. a

$$9+5b-2a$$