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Question
Let V (x, y, z) = xy + yz + zx, x, y, z ∈ R. Find the differential dV
Solution
V(x, y, z) = xy + yz + zx
Vx = y + z
Vy = x + z
Vz = y + x
The differential is dV = (y + z)dx + (x + z)dy + (y + x)dz
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