The Trigonometry TI-83/TI-84 Tutorial uses four special characters frequently, the Greek letters delta, pi and theta, and the degree symbol. These characters have been specified in the HTML code using universal character set (unicode) references, which is a way of designating a character that is independent of a font type. In most cases, getting your browser to properly display these characters is simply a matter of choosing an appropriate font in your browser. The following table offers a few common fonts that should be able to interpret the four characters used in this tutorial correctly (different fonts will handle different ranges of unicode values).
| SYSTEM | Windows | Mac |
|---|---|---|
| FONTS | Arial Unicode MS Times New Roman Lucida Sans Unicode |
Tahoma |
Try choosing some different fonts in your browser until the set of characters shown below are all displayed properly (the decimal versions are given for reference).
| Δ (delta: #916), π (pi: #960), ∞ (infinity: #8734), ≈ (approximately: #8776) |
Here are some links to internet web resources that provide information about Unicode and instructions for setting the fonts in various browsers.
Getting Started : Unicode
Unicode Capable Browsers
Unicode Fonts
Enabling Unicode in Various Browsers
For more information on unicode fonts, you might try the following internet resources which go into greater detail. If all else fails, then you may need to update your browser to a more current version or switch to a different browser.
Data Recovery Labs - Unicode Fonts
The Unicode Consortium
Alan Wood's Unicode Resources