Question

Factorize:

(i) (l+m)2 – (l-m)2​

Answer 1

Answer:

${(l + m)}^{2} - {(l - m)}^{2} \\ = ( {l}^{2} + {m}^{2} + 2(l)(m)) - ( {l}^{2} + {m}^{2} - 2(l)(m)) \\ = \cancel{{l}^{2}} + \cancel{ {m}^{2} } + 2lm \cancel{- {l}^{2}} \cancel{ - {m}^{2}} + 2lm \\ = \: \: \underline{ \underline{4lm}}$

Answer 2

Answer:

4lm

Step-by-step explanation:

(l+m)² - (l-m)²

=(l² + 2lm + m²)  - (l²- 2lm +m²)

= l² + 2lm + m² -l² + 2 lm - m²

plus and minus will get cancelled

i.e l² - l² = 0,  m² - m² =0

therefore, 2 lm + 2lm = 4lm