tanx=sinx/cosx，

When x = 90,

That is, Tan90 = Sin90/Cos90.

= 1/0

Denominator cannot be 0,

No tan90.

Tan90 is a very popular emoticon pack in Weibo. It first originated in Utopia, when the betta anchor "Five Lakes and Volts" was broadcast live.

In case of losing, I will say "does not exist, will beat me, does not exist!" " When the enemy hero wants to kill him, he will also say "does not exist" and then be hit in the face in an instant ... This mantra became popular and became an expression pack.

So tan90 means: it doesn't exist! Can also be understood as: impossible, useless, unnecessary.