TAYLR

This operation calculates an approximation of the Taylor series of the input expression at zero. The symbol argument indicates what symbol should be used to evaluate the Taylor series against. The real argument should be a positive integer value which is the degree of the Taylor series to create.

To successfully calculate the Taylor series, the expression and the first nth derivatives of that expression must have a real value at 0. If you want to evaluate an expression of X at some other value, for example at 3, then you could set X to the expression 'Y+3' and then evaluate your expression. This should substitute all X's in your expression with 'Y+3'. Then, you can get the Taylor series against Y. Finally, you can clear the value of X and set Y to 'X-3' and evaluate the result to get an expression in terms of X again.