A case against the x<>y key

[Thomas Klemm]

You could use the calculation of cos(x) as a practical example:

\(\begin{align*}
\cos(x) &= 1-\frac{x^2}{2!}+\frac{x^4}{4!}-\frac{x^6}{6!}+\frac{x^8}{8!}-\frac{x^{10}}{10!}+O(x^{12})\\
&= 1-\frac{x^2}{1\cdot2}(1-\frac{x^2}{3\cdot4}(1-\frac{x^2}{5\cdot6}(1-\frac{x^2}{7\cdot8}(1-\frac{x^2}{9\cdot10}))))+O(x^{12})
\end{align*}\)

Using the x<>y key:

x² ENTER ENTER ENTER
90 ÷ 1 x<>y −
× 56 ÷ 1 x<>y −
× 30 ÷ 1 x<>y −
× 12 ÷ 1 x<>y −
× 2 ÷ 1 x<>y −


Using the CHS key:

x² CHS ENTER ENTER ENTER
90 ÷ 1 +
× 56 ÷ 1 +
× 30 ÷ 1 +
× 12 ÷ 1 +
× 2 ÷ 1 +


Kind regards
Thomas