you can switch to "fraction calculator" in the highlighted menu:
you can use the built in "equation solver" to verify your solutions:
http://web2.0rechner.de/formelsammlung/mathematik/geometrie/kugel
http://de.wikipedia.org/wiki/Kugel
log4(16)
$${factorize}{\left({\mathtt{84}}\right)} = \left\{ \begin{array}{l}{\mathtt{4}} = {{\mathtt{2}}}^{{\mathtt{2}}}\\ {\mathtt{3}}\\ {\mathtt{7}}\\ \end{array} \right\}$$
22x-16=18xbeide Seiten: -18x22x-16-18x=18x-18x22x-18x-16=18x-18x4x-16=0beide Seiten: +164x-16+16=0+164x=16beide Seiten: /44x/4=16/4(4/4)*x=16/4(1/1)*x=41*x=4x=4Probe:
22*4-16=18*488-16=7272=72
it's the ÷ button.
Example fraction addition: 1/3 + 2/5
$${\frac{{\mathtt{1}}}{{\mathtt{3}}}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{2}}}{{\mathtt{5}}}}$$
how to delete calculation history
now a "clear history" link is available in the expanded history dropdown
try using the circle formulas in the formulary section: