Question

four important identities

Answer 1

Answer:

$\huge\sf \underline{identities : -}$

$\sf (i) \: \: \: \: \: \: \: {(x + y)}^{2}$

$\sf \to {x}^{2} + 2xy + {y}^{2}$

$\sf (ii) \: \: \: \: \: \: \: \: {(x - y)}^{2}$

$\sf \to {x}^{2} - 2xy + {y}^{2}$

$\sf (iii) \: \: \: \: \: \: \: {x}^{2} - {y}^{2}$

$\sf \to (x + y)(x - y)$

$\sf (iv) \: \: \: \: \: \: \: \: (x + a)(x + b)$

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

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Answer 2

Answer:

Identity I: (a + b)2 = a2 + 2ab + b2

Identity III: a2 – b2= (a + b)(a – b)

Identity IV: (x + a)(x + b) = x2 + (a + b) x + ab.

Identity V: (a + b + c)2 = a2 + b2 + c2 + 2ab + 2bc + 2ca.

Identity VI: (a + b)3 = a3 + b3 + 3ab (a + b)