Module "Cubic Functions" of program "Ruler and Compass" of Literka

Download "Ruler and Compass" version 1.5.



Let us present a screenshot of output of one of examples of module "Cubic Functions" of program "Ruler and Compass"


We can see a formula of a cubic function. (Created with a use of a command "CubicFunct".)
Then there is another formula of a cubic function (created by a command ”DrawSimplCubFunct”). This formula is received by substitution of a new variable x’=(x-1/6)/8. Next, there are two roots of first cubic function (created with a command CubEqRoot).
We can see also graph of our cubic function. At the bottom there are two strings, which show numerical values of roots of cubic equation. (Set by command ”DrawRootValue”). They show values with accuracy of (up to) 40 significant digits.

There are some restrictions on creating of cubic functions. Coefficients cannot be too large. In the case coefficients are too large a runtime error message is issued ”Coefficients are too large. Major error may occur”. In that case roots formulas will not be shown.
It may happen even with small-looking coefficients. In that case we should use a command ”ValCubFunct” instead of ”CubicFunct”. Then we can get at least numerical values of roots. See examples provided by Literka.