~~NOTOC~~
<=[[4rpl:start| Index]] \\
<= [[4rpl:start#Math]]  

====== cos ======
cos(<-angle) ->cosAngleRadians

===== Description =====
Calculates the cosine of the input angle in radians

===== Examples =====
<code 4rpl>
trace(cos(PI)) #prints '-1'
</code>
<=[[4rpl:start| Index]]