# Mathematical expressions input rules

## Numbers input:

One can input integer numbers in the common way, for example: 4; 18; 56

To input the negative number it is necessary to put the minus sign before the number: -19; -45; -90

Rational numbers are entered by means of the / symbol, for instance: 3/4;
-5/3;
5/(-19)

Decimal numbers can be entered by using the dot as the separator of integer and decimal parts of the number: 4.5;
-0.4

## Variables and constants input:

Variable and constants are entered be means of latin letters, for example: x; y; z;
a; b.

To enter the variable one can also use the integer numbers after the correspon letter: x1;
y3;
a4.

Constants π and e can be input as pi and e - correspondingly.

Infinity symbol ∞ are entered with two small oo latin latters or by means of the inf word.

The plus infinity and the minus infinity are entered as +oo and -oo correspondingly.

## Addition and subtraction:

Addition and subtraction are entered by means of the + and - signs correspondingly, for instance: 3+a; x+y; 5-4+t; a-b+4; ATTENTION! No space are needed between the operands, for example the input: x + a is wrong, the right input is x+a - without the spaces.

## Verify yourself, input the expression:

## Others useful links:

Taylor series expansion onlineSimplify math expression online

Decart plot online