Question

factorise
(l+m)^2 -(l-m)^2
​

Answer 1

Answer:

$\red{ (l+m)^{2} - (l-m)^{2}} \green { = 4lm}$

Step-by-step explanation:

(l+m)² - (l-m)²

= [ (l+m) + (l-m)][(l+m) - (l-m)]

$\boxed { \pink { a^{2} - b^{2} = (a+b)(a-b) }}$

= ( l + m + l - m )( l + m - l + m )

= 2l × 2m

= 4lm

Therefore.,

$\red{ (l+m)^{2} - (l-m)^{2}} \green { = 4lm}$

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