[b] f(x, y) = 3 exp(-(y+1)[sup]2[/sup]-x[sup]2[/sup]) (x-1)[sup]2[/sup]-exp(-(x+1)[sup]2[/sup]-8[sup]2[/sup])/3+exp(-x[sup]2[/sup]-y[sup]2[/sup]) (10x[sup]3[/sup]-2 x+10y[sup]5[/sup]) [br][size=85]*Detailed instructions and explanations for this applet can be found in the previous applets [url=https://www.geogebra.org/m/yf62eg4c]1[/url], [url=https://www.geogebra.org/m/v6pwykyh]2[/url] and [url=https://www.geogebra.org/m/djtadvjc]3[/url].[/size][/b]