I hope I can get some help understanding the math of this problem. The problem is 2x^(2/3) + y^(2/3). I did this: d/dx (y^2/3) = -d/dx ((-2x^(2/3). I come up with dy/dx = -2x^(2/3)/y^(2/3). My graphing claculator says the answer is -2y^1/3)/x^(1/3). Can someone please help me understand the math that comes up with the solution on my calculator, or am I just doing this wrong?