I just learnt Google can be used as a 2D-3D Graphing Calculator. Try this out:

Go to Google and type: x^2

(x+y)^2:

(x^2+y^2):

sin(x+y):

cos(x) + 1/2 cos(2x) + 1/4 cos(4x)

z=x^2-y^3

x/(1+x^2)*(1+y^2)

graph x^2 and sqrt(x)

I don’t know if I’ll ever use this feature, but good to know this exists.