numworks / epsilon

Modern graphing calculator operating system.
https://www.numworks.com/resources/engineering/software/
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Exact Solutions to Cubics #2188

Open jrkimber opened 4 months ago

jrkimber commented 4 months ago

Hi,

Currently the Numworks gives solutions to equations in the form ax^3 + bx^2 +cx +d = 0, where d =/= 0 as decimals. For example, the following equation:

screenshot (67) screenshot (66)

It would be a useful improvement if it could give exact solutions as it does currently for quadratics and cubics where d=0.

Thanks, James

adri1numworks commented 2 months ago

Hello, This is due to our current way of solving equations numerically. We basically put a threshold above which our algorithm considers the calculation is going to be too complicated to solve exactly. I am creating a ticket internally and we'll see if we can improve this threshold. If yes, we will be able to give exact results for "more" equations.