You can enter your own multivariable function in the input box at bottom right.[br][b][br][color=#1e84cc]To explore in Augmented Reality, see the directions below the applet. [/color][/b]

1) Open up GeoGebra 3D app on your device. [br][br]2) Go to MENU (3 horizontal bars in upper left hand corner). [br][br]3) Select OPEN. Under search, type: [b]fgzyyx8x[/b][br][br]4) The sliders [b]a & b[/b] control the [b]x & y[/b] coordinates of the point (respectively).[br] You will also see [b]FILLING sliders [/b]to fill in the surface itself or the tangent plane. [br][br]5) To switch from partial derivative with respect to [i]x[/i] and partial derivative with respect to [i]y[/i], [br] adjust the slider named [b]whichpartialderiv [/b]at the bottom of the algebra pane.