Press button in right-top corner to enter settings. Drag buttons with writings: sin; cos; tan; {\displaystyle \surd } {\displaystyle \surd } ; {\displaystyle \surd } {\displaystyle \surd } ->+ ; ( ; ) ; 2; 3; X; X1; Z; Z1, to make formula. Press button in right-bottom corner to exit settings. Press button with rainbow pen on it, wait some time, and watch how it draws. If you want to emergency stop drawing, press button with red octagon on it (at right side). On the left side you can see max and min variable and colors between them.
Create surface with math. v. 0.0.0.1 first ROUND earth. 29.06.2019.