Question

please tell the four important identities5​

Answer 1

Answer:

Identity - [i]

$\sf {(x + y)}^{2} = {x}^{2} + 2xy + {y}^{2}$

Identity - [ii]

$\sf {(x - y)}^{2} = {x}^{2} - 2xy + {y}^{2}$

Identity - [iii]

$\sf(x + y)(x - y) = {x}^{2} - {y}^{2}$

Identity - [iv]

$\sf(x + a)(x + b) = {x}^{2} + x(a + b) + ab$