What is the value of the given expression?
(a + b + c)2 - a2 - b2 - c2
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 2(ab + bc + ca).
(a + b + c)2 - a2 - b2 - c2
Formulae:
⇒ (a + b + c)2 = a2 + b2 + c2 + 2(ab + bc + ca)
Now according to the question
(a + b + c)2 - a2 - b2 - c2
⇒ a2 + b2 + c2 + 2(ab + bc+ ca) - a2 - b2 - c2
⇒ 2(ab + bc + ca)