The value ofis

11

If 3x=a+b+c, then the value of (x-a)³+(x-b)³+(x-c)³-3(x-a)(x-b)(x-c) is

12

If (x+y)³-(x-y)³-6y(x²-y²)=ky² then k=

13

Ifx³-3x²+3x-7=(x+1)(ax²+bx+c), then a+b+c=

15

The value of is