Factorization a2-2ab+b2=(a-b)2

Factorization

a2-2ab+b2=(a-b)2

Example 1

$$\textup{Factorize } x^2-4x+4 $$

Solution

\begin{align*} &\because\;\; a^2-2ab+b^2=(a-b)^2 \\\\ &\therefore\;\; x^2-4x+4 \\ &=(x)^2-2(x)(2)+(2)^2 \\ &=(x-2)^2 \\ \end{align*}

Example 2

$$\textup{Factorize } z^2-10z+25 $$

Solution

\begin{align*} &\because\;\; a^2-2ab+b^2=(a-b)^2\\\\ &\therefore\;\; z^2-10z+25 \\ &=(z)^2-2(z)(5)+(5)^2 \\ &=(z-5)^2 \\ \end{align*}

Example 3

$$\textup{Factorize } 9x^2-24x+16 $$

Solution

\begin{align*} &\because\;\; a^2-2ab+b^2=(a-b)^2 \\\\ &\therefore\;\; 9x^2-24x+16 \\ &=(3x)^2-2(3x)(4)+(4)^2 \\ &=(3x-4)^2 \\ \end{align*}

Example 4

$$\textup{Factorize } 4y^2-20y+25 $$

Solution

\begin{align*} &\because\;\; a^2-2ab+b^2=(a-b)^2\\\\ &\therefore\;\; 4y^2-20y+25 \\ &=(2y)^2-2(2y)(5)+(5)^2 \\ &=(2y-5)^2 \\ \end{align*}