Question

Expands using suitable identities (b-2)²

Answer 1

Step-by-step explanation:

using identity

$\huge(a - b) {}^{2} = a {}^{2} - 2ab + b {}^{2}$

here

$a = b \: and \: b = 2$

$= (b) {}^{2} - 2(b)(2) + (2) {}^{2}$

$\huge = b {}^{2} - 4b + 4 \: \: ans.$

Answer 2

To expand : $(b - 2 )^{2}$

Solution :

• To expand $(b - 2 )^{2}$  we apply the identity  of $(x - y ) ^{2} = x^{2} - 2xy + y^{2}$ .

        Here , $x = b$ and $y = 2$  

• Substituting the values we expand the above expression.

          $(b -2 )^{2} = b^{2} - 2 (b ) (2 ) - (2)^{2}$

                      $= b^{2} -4b + 4$

Hence, expansion of $(b - 2 )^{2}$  is $b^{2} -4b + 4$ .