Spacetime 3.0 - The basic tricks

Spacetime is the best calculator for iPod/iPhone I know. It's not only a calculator, Spacetime also includes a 2D/3D plotter, equation solver, mathematical constants, loads of functions, allows you to write your own functions by scripting them; Spacetime is able to work with fractions, complex numbers and so. I would like to show you how to use the basic functions and how to save your time.

Writing (only iPod/iPhone)
This feature works only for these two devices, turn your ipod into landscape position; a keyboard appears and you can write difficult equations and commands much easier.



Fractions
Spacetime is able to return a result as a fraction. For example sinus(π/4) returns √2/2 and 0.7071... if you click once more the 'Solve button' or the "N" icon.



Plot two or more graphs into one image
Sometimes it's useful to see more graphs in one image. For instance let's say you want to plot the three-phase current. In fact we will plot three sinus graphs with 2π/3 offset. The trick to plot more graphs together is in separating them with a comma.

Plot(sin(x),sin(x+2π/3),sin(x+4π/3))

And you get the result.



Roots
Maybe there is a better way but I couldn't find an easier way. For example you want to get the fifth root of 32. Here is my solution:

5√32 //doesn't work, returns 5*√32
32^(1/5) //works fine, returns 2

Solving quadratic equations quickly
The most effective and also fastest way I know to solve a quadratic equation actually comes from the tutorial but it's useful to remember the syntax. There are two alternatives how to solve a quadratic equation (e.g. 3x^2+5x-2)

Solve(3x^2+5x-2)
Solve(3,5,-2)

The second one is the tricky way. Logically, you insert three variables (a,b,c) ax^2+bx+c. If for instance b=0, you insert 0 as the second parameter. Very useful shorthand.



Expand() function
Stuff like (a+b)^3 seems to be not working in Spacetime, right? Fortunately we have the expand() function. The usage is very easy, expand() function has only one parameter and it's the expression you want to solve (a+b)^n, n stands for a natural number (or maybe a fraction too? I have no experience).



I'm sure you will take a fancy to Spacetime soon. The best thing is that it is portable to many pocket devices including iPod and iPhone. But you can also use Spacetime on your PC or even Mac with no restrictions. Visit the home page of SpaceTime to get more information.