Solutions to Examples on Partial Derivatives
math.gmu.edu › Fall08 › partDerivExamplesSolutions to Examples on Partial Derivatives 1. (a) f(x;y) = 3x+ 4y; @f @x = 3; @f @y = 4. (b) f(x;y) = xy3 + x 2y 2; @f @x = y3 + 2xy2; @f @y = 3xy + 2xy: (c) f(x;y) = x 3y+ ex; @f @x = 3x2y+ ex; @f @y = x. (d) f(x;y) = xe2x +3y; @f @x = 2xe2x+3 + e 2x y; @f @y = 3xe . (e) f(x;y) = x y x+ y: @f @x = x+ y (x y) (x+ y)2 = 2y (x+ y)2; @f @y = (x+ y) (x y) (x+ y)2 = 2x (x+ y)2. (f) f(x;y) = 2xsin(x2y): @f