Expand:
(4a + 3b + 2c)2
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e 16a2 + 9b2 + 4c2 + 24ab + 12bc + 16ca
⇒ (4a + 3b + 2c)2
Let x = 4a + 3b & y = 2c
⇒ (x + y)2 = x2 + 2xy + y2
⇒ (4a + 3b + 2c)2 = (4a + 3b)2 + (2c)2 + 2(4a + 3b)(2c)
⇒ (4a + 3b + 2c)2 = 16a2 + 24ab + 9b2 + 4c2 + 16ac + 12bc