Question

(x+y+z)^3-(y+z-x)^3-(z+x-y)^3-(x+y-z)^3-23xyz , x=2019,y=2020,z=1/2020

Answer 1

Answer:

Step-by-step explanation:answer is 2019

As X=y-1, y=y, z=1/y.

Pit these in equation,

=(2y-1+1/y)³-(1/y+1)³-(1/y-1)³-(2y-1-1/y)³-23(y-1)

=(2/y³)+6(2y-1)²/y -2/y³-6/y-23(y-1)

=6(2y-1)²/y - 23(y-1) -6/y

=24y-24-23y+23

=y-1

=2019