Question

If x=a+b-c, y=b+c-a, z= -2b then x^3 + y^3 +z^3 is equal to:

Answer 1

Solution:

/* we know that,

If x+y+z=0 then

x³+y³+z³ = 3xyz */

Here ,

x = a+b-c ,

y = b+c-a,

z = -2b

Now ,

x+y+z

= a+b-c+b+c-a-2b

= 0

Therefore,

x³+y³+z³

= 3xyz

= 3(a+b-c)(b+c)(-2b)

= -6b(b+c)(a+b-c)

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