Q440
If (2x + 3)3 + (x - 8)3 + (x + 13)3 = (2x + 3)(3x - 24)(x + 13), what is the value of x?
A.
-2
AnswerB.
-2.5
C.
-1
D.
-1.5
Answer: Option A
Solution
Answer: Option A
Solution:
(2x + 3)3 + (x - 8)3 + (x + 13)3 = 3(2x + 3)(x - 8)(x + 13)a3 + b3 + c3 - 3abc = 0 {If a + b + c = 0}
2x + 3 + x - 8 + x + 13 = 0
4x + 8 = 0
x = -2