\hspace{-16}$Show that regardless of what Integer values of $\mathbf{x\;,y}$ Substituted\\\\ in $\mathbf{x^5-x^4y-13x^3y^2+13x^2y^3+36xy^4-36x^5}$ is never equal to $\mathbf{77}$
71Yes, I think it should be.
It it is so, then we can easily factor out the expression into 3 distinct expressions while the RHS being a prime no. has only 2 distinct factors.
Hence it's never equal to 77
1057the given expression factorises into (x-y)(x+2y)(x-2y)(x-3y)(x+3y)
since 77(excluding itself) has only three factors nd neither of de 4 terms for any integer value of x and y are same therefore de product of dese 4 terms cant be 77 or for that matter any number that is prime or has less than 4 factors excluding itself....
