The LCM of two numbers x and y is z. What is their HCF?
yz/x
xy/z
xz/y
xyz
We know that for two positive integers x and y, LCM (x,y) × HCF(x,y)=x × y
Hence the answer is
If x+y+z=8 and xy+yz+zx=20, find the value of x3+y3+z3−3xyz.