Simplify the following expression.
(2a - b - 3c) (4a2 + b2 + 9c2 + 2ab + 6ac - 3bc)
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 8a3 - b3 - 27c3 - 18abc
(2a - b - 3c)(4a2 + b2 + 9c2 + 2ab + 6ac - 3bc)
⇒ 8a3+2ab2+18ac2+4a2b+12a2c−6abc−4a2b−b3−9bc2−2ab2−6abc+3b2c−12a2c−3b2c−27c3−6abc−18ac2+9bc2
⇒ 8a3−18abc−b3−27c3
The simplified expression for (2a - b - 3c) (4a2 + b2 + 9c2 + 2ab + 6ac - 3bc) is 8a3 - b3 - 27c3 - 18abc.