You can grab the blue point in the x-y plane and move it around to see how the partial derivatives change. [br][br]The red line is the line whose slope computes [math]\frac{\partial f}{\partial x}[/math]; the green line is the line whose slope computes [math]\frac{\partial f}{\partial y}[/math]. Both slopes are displayed whenever the corresponding line is.[br][br][br]Use the toggle switches to change visibility:[br][br]graphvisible turns the graph of f on and off.[br]xslicevisible turns the y=constant slice (in which we compute [math]\frac{\partial f}{\partial x}[/math]) on and off.[br]yslicevisible turns the x=constant slice (in which we compute [math]\frac{\partial f}{\partial y}[/math]) on and off.[br]xtangentvisible turns the tangent line whose slope is [math]\frac{\partial f}{\partial x}[/math] on and off.[br]ytangentvisible turns the tangent line whose slope is [math]\frac{\partial f}{\partial y}[/math] on and off.[br][br]Enter your own function in place of the default [math]f\left(x,y\right)=sin\left(x\right)-y^3[/math].