TAN() function

SELECT TAN( X )

TAN() with PI()

SELECT ROUND(TAN(PI()),2); // Ouput is -0.00
SELECT TAN(PI()/2); // Ouput is 1.6331239e+16 or infinity 
SELECT ROUND(TAN(PI()/3),2); // Ouput is 1.73 

TAN() with RADIANS

Radians function convert degree value to radian.

SELECT TAN(RADIANS(0)); // Ouput is 0
SELECT TAN(RADIANS(45)); // Output is 1 
SELECT TAN(RADIANS(90)); // Output is infinity or 1.63312393531954e+016
SELECT ROUND(TAN(RADIANS(180)),2); // Output is -0.00