Type any expression and you'll see the graph.You can choose the x interval (e.g. x=from -1 to 20) and the step. Available functions are :
COS, SIN, SINH, COSH, TAN, COTAN, ARCTAN, ARG,EXP, LN, LOG10, LOG2, LOGN, SQRT, SQR, POWER, INTPOWER,MIN, MAX, ABS, TRUNC, INT, CEIL, FLOOR ,RANDOM and
SIGN (sign(x) is 1 for x>1, 0 for x=0, -1 for x0 and =0 for x
