
Premi qui per la versione italiana
G E O M E T R I A
by Elf Qrin
This program helps students,
to solve their homeworks of geometry,
computing lines, surfaces and volumes of the main plane and solid figures,
through direct and indirect formulas.
It should be considered as a tool, such as the calculator, to solve problems, but
it can't "automagically" solve them by itself. Often some reasoning is required to find the correct calculation.
To use this tool, select the figure you are working on, choose the kind of calculation from the list, and then click the Compute button and input the requested data.
For example, to calculate the height of a triangle of which you know area and base, select the triangle first, by clicking on the little radio button on the left,
then choose Find "Height, given area and base" from the list on the right, then press the "Computed" button situated below, enter area and base when prompted for them,
and you'll get the area with formulas and all in the results window.
When you are requested to input data you can give a formula (or expression), rather than a simple number:
For example, when asked to input the height of a triangle (or any other data),
instead of 3, you can put 2+1, or (2+7)/3.
If you previously inserted another data, such as the base (identified by B, see below)
you can input a formula like 2/3*B, meaning thus that the height
of that triangle is 2/3 of the base.
Furthermore, you can use common mathematic functions such as
sqrt (square root), sin (sine), cos (cosine), tan (tangent).
For example, you can put sqrt(140+4) instead of 12, since the square root of 144 is 12.
To calculate the power of a number, you have to use the function pow(x,y), thus 5+2^3 must be entered as 5+pow(2,3).
It's important to enter mathematic function in lower case and variables in upper case, otherwise they won't be recognized and you'll get an error message.
Under the Results window there's an input area that can be used as a calculator, in which you can write a formula, in the same way stated before, then you can click on Compute Formula to show the result.
If in the Results window are shown the results of a previous calculation about a geometric figure, you can use those variables inside your formula.
The following rules are used to assign the names to the variables that identify geometric elements:
Elements like Base, Height, Diagonal, Area, Perimeter and Volume are commonly identified by their initials, thus: B, H, D, A, P, V.
The side is identified by letter L (from the Latin word "Latus").
To the letter that identifies an element, a second one may follow, identifying the figure (in Latin) to which that element belongs: for example the Diagonal of the Square is identified as DQ (from the Latin "Quadratum").
Major and minor Diagonals are identified by DG and DP ("Grandis" and "Parvus", in Latin).
I used Latin names because I wrote this program in Italian first, due to the necessity to test it with real homeworks of the local kids.
Anyway names of the variables shouldn't be a problem, since when you know what they means, you can write whatever you want on your notebook or exercise book.
I wish to thank my friend Alessandro Rudellat for helping me during the beta testing,
letting me try this program with his homeworks... I suspect he enjoyed it too... :^)


A cheerful friend is like a sunny day.
Department of Redundancy Department

