Polynomials

A polynomial of degree n has the form:

P(x)=a_nx^n+a_{n-1}x^{n-1}+ \cdots +a_1x+a_0

Long Division Polynomials

\frac{x^2+7x-9}{x+2}

Write in long division format

x+2 \overline{\smash{\big)}x^2+7x-9}

Divide the leading term of the dividend by the leading term of the divisor \frac{x^2}{x}=x

Write x at the top and multiply by x+2. Subtract from divident.

\begin{array}{c} x \\ x+2{\overline{\smash{\big)}\,x^2+7x-9\phantom{)}}}\\ \underline{-~\phantom{(}(x^2+2x)\phantom{-b)}}\\ 0+5x-9\phantom{)}\\  \end{array}

Divide the leading term of the obtained remainder by the leading term of the divisor \frac{5x}{x}=5

Write +5 at the top and multiply by x+2. Subtract from divident.

\begin{array}{c} x+5 \\ x+2{\overline{\smash{\big)}\,x^2+7x-9\phantom{)}}}\\ \underline{-~\phantom{(}(x^2+2x)\phantom{-b)}}\\ 0+5x-9\phantom{)}\\ \underline{-~\phantom{()}(5x+10)}\\  0-19\phantom{)} \end{array}

Divide the obtained remainder by the divisor and add to the answer.

Therefore:

\frac{x^2+7x-9}{x+2}=x+5+\frac{-19}{x+2}