Question

how to factorise a^2 + 4a+ 2​

Answer 1

${a}^{2} + 4a + 2 \\ \\ = {a}^{2} + 4a + 4 - 2 \\ \\ = {(a + 2)}^{2} - 2 \\ \\ = {(a + 2)}^{2} - {( \sqrt{2} )}^{2} \\ \\ = (a + 2 - \sqrt{2} )(a + 2 + \sqrt{2} ) \\ \\ \\ \\ formulae \\ \\ \\ {(x + y)}^{2} = {x}^{2} + {y}^{2} + 2xy \\ \\ {x}^{2} - {y}^{2} = (x - y)(x + y)$

$\color{blue}{ \bold{ {\mathfrak{hope \: it \: helps}}}}$