Trigonometric ratios of 90 degrees

Here are the exact values of the trigonometric ratios of an angle of 90 degrees

${\displaystyle \sin <!--\; \; -->90°=1}$

${\displaystyle \cos <!--\; \; -->90°=0}$

${\displaystyle \tan <!--\; \; -->90°=\mathrm{undefined}}$