## The Mathematical Symbol "Spherical Angle (∢)"

The "Spherical Angle" Symbol (∢)

The ∢ symbol is known as the "Spherical Angle". It represents an angle formed by three great circles on a sphere.

## Understanding the Symbol

The ∢ symbol resembles a curved angle, indicating its spherical nature. Unlike the common plane angle, a spherical angle is a measure of rotation between three distinct points on the surface of a sphere.

## Usage

Spherical angles are crucial in the fields of geometry, particularly spherical geometry, and trigonometry. They have applications in cartography, navigation, and various other fields where understanding the Earth's surface and other spherical surfaces is essential.

When defining a point on the Earth's surface, for instance, one might use latitude and longitude lines, which create spherical angles at the Earth's core.

## Example

Imagine you are plotting three cities on a globe: City A, City B, and City C. The spherical angle at City A, formed by the arcs connecting City A to City B and City A to City C, would be represented using the ∢ symbol.

## Typing ∢

In digital documents or web-based platforms, using the ∢ entity will render the "Spherical Angle" symbol. Depending on the specific mathematical software, notation system, or programming environment, there might be different methods to input and display this symbol.

## Related Symbols

Related symbols to consider include ∠ (Angle) which represents a plane angle. There's also ∟ (Right Angle) which is a specific measure of 90° or π/2 radians. These symbols offer clarity in distinguishing between different types of angles and their representations.

## Conclusion

The ∢ symbol, or the Spherical Angle, is essential for conveying distinct measures and relationships on spherical surfaces. Knowing when and how to use it ensures clarity and precision in mathematical and geographical discussions.

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## Codes for the ∢ Symbol

 The Symbol ∢ Alt Code Alt 8738 HTML Code ∢ HTML Entity ∢ CSS Code \2222 Hex Code ∢ Unicode U+2222

## How To Insert the ∢ Symbol

(Method 1) Copy and paste the symbol.

The easiest way to get the ∢ symbol is to copy and paste it into your document.

Bear in mind that this is a UTF-8 encoded character. It must be encoded as UTF-8 at all stages (copying, replacing, editing, pasting), otherwise it will render as random characters or the dreaded �.

(Method 2) Use the "Alt Code."

If you have a keyboard with a numeric pad, you can use this method. Simply hold down the Alt key and type 8738. When you lift the Alt key, the symbol appears. ("Num Lock" must be on.)

(Method 3) Use the HTML Decimal Code (for webpages).

HTML TextOutput
<b>My symbol: &#8738;</b>My symbol: ∢

(Method 4) Use the HTML Entity Code (for webpages).

HTML TextOutput
<b>My symbol: &angsph;</b>My symbol: ∢

(Method 5) Use the CSS Code (for webpages).

CSS and HTML TextOutput
<style>
span:after {
content: "\2222";}
</style>
<span>My symbol:</span>
My symbol: ∢

(Method 6) Use the HTML Hex Code (for webpages and HTML canvas).

HTML TextOutput
<b>My symbol: &#x2222;</b>My symbol: ∢
On the assumption that you already have your canvas and the context set up, use the Hex code in the format 0x2222 to place the ∢ symbol on your canvas. For example:
JavaScript Text
const x = "0x"+"E9"
ctx.fillText(String.fromCodePoint(x), 5, 5);
Output

(Method 7) Use the Unicode (for various, e.g. Microsoft Office, JavaScript, Perl).

The Unicode for ∢ is U+2222. The important part is the hexadecimal number after the U+, which is used in various formats. For example, in Microsoft Office applications (e.g. Word, PowerPoint), do the following:
TypeOutput
2222
[Hold down Alt]
[Press x]

(The 2222 turns into ∢. Note that you can omit any leading zeros.)
In JavaScript, the syntax is \uXXXX. So, our example would be \u2222. (Note that the format is 4 hexadecimal characters.)
JavaScript TextOutput
let str = "\u2222"
document.write("My symbol: " + str)
My symbol: ∢