Formula use: \left(a-b\right)^3=a^3-3a^2b+3ab^2-b^3

Explanation

Here, given expression is : x – y – z
Now, Find the cubes of :
\{\left(x-y\right)-z\}^3
\rightarrow\left(x-y\right)^3-3.\left(x-y\right)^2.z+3.\left(x-y\right).\left(z\right)^2-\left(z\right)^3
\rightarrow\left(x^3-3.x^2.y+3.x.y^2-y^3\right)-3.\left(x^2-2xy+y^2\right).z+3.\left(x-y\right).z^2-z^3
\rightarrow\left(x^3-3x^2y+3xy^2-y^3\right)-3x^2z+6xyz-3y^2z+3xz^2-3yz^2-z^3
\rightarrow x^3-3x^2y+3xy^2-y^3-3x^2z+6xyz-3y^2z+3xz^2-3yz^2-z^3
Ans: x^3-3x^2y+3xy^2-y^3-3x^2z+6xyz-3y^2z+3xz^2-3yz^2-z^3\ .