Question

(x+y)2 = (x-y)2 + 4xy = how?
please answer quickly​

Answer 1

Answer:

(x-y)^2=(x+y)^2-4xy

LHS (x-y)^2 = x^2 -2xy +y^2

RHS (x+y)^2- 4xy

=(x^2 +2xy + y^2) - 4xy

=x^2 +2xy+ y^2 - 4xy

=x^2 + 2xy- 4xy + y^2

=x^2 - 2xy + y^2

Answer 2

$\bf\huge\underline{\underline{ To \: Prove :- }}$

• (x+y)² = (x-y)² + 4xy

$\bf\huge\underline{\underline{ Answer :- }}$

• if (x+y)² = (x-y)² + 4xy ,

• (x + y)² - (x-y)² = 4xy

$\rule{10cm}{0.05cm}$

• ( x + y ) ² = x² + y² + 2xy

• ( x - y)² = x² + y² - 2xy

$\rule{10cm}{0.05cm}$

(x+y)² - (x-y)² = x²+y²+2xy -(x² + y² - 2xy )

• $\red{\implies}$ x² -x² + y²-y²+2xy+2xy

• $\red{\implies}$ 4xy

$\rule{10cm}{0.05cm}$

Hence , (x+y)² = (x-y)² + 4xy