If x3 + 4y3 + 9z3 = 18xyz and x + 2y + 3z = 0 ; evaluate
(x+2y)2xy+(2y+3z)2yz+(3z+x)2zx
Given that x3 + 4y3 + 9z3 = 18xyz and x + 2y + 3z = 0
∴ x + 2y = - 3z, 2y + 3z = -x and 3z + x = -2y
(x+2y)2xy+(2y+3z)2yz+(3z+x)2zx=(−3z)2xy+(−x)2yz+(−2y)2zx
= 9z2xy+x2yz+4y2zx
= x3+4y3+9z3xyz
Given that x3 + 4y3 + 9z3 = 18xyz
∴(x+2y)2xy+(2y+3z)2yz+(3z+x)2zx=18xyzxyz
= 18