1. The problem statement, all variables and given/known data Find the linear approximation of (xy)/z at the point (-3,2,1) 3. The attempt at a solution So the example my book gives has 2 variables so i'm struggling a bit with this, But I started off by taking the partial derivative with respect to each variable and solving for it. d/dx = (y/z) = 2 = A d/dy = (x/z) = -3 = B d/dz = -(xy)/z^2 =6 = C now... find the equation of a plane passing through that point maybe? A(x-xo)+B(y-yo)+C(z-zo) = 0 2(x+3) - 3(y-2) + 6(z-1) = 0 2x+6 - 3y+6 +6z-6 = 0 2x-3y+6z+6=0 am I on the right track here..?