Simplify: (2a - 3b - c)2 - (a + 2b + c)2
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 3a2 + 5b2 - 16ab + 2bc - 6ac.
(2a - 3b - c)2 - (a + 2b + c)2
= (2a - 3b - c + a + 2b + c)(2a - 3b - c - a - 2b - c)
= (3a - b)(a - 5b - 2c)
= 3a2 + 5b2 - 16ab + 2bc - 6ac
Hence, the value of the expression is 3a2 + 5b2 - 16ab + 2bc - 6ac.