sin, cos and tan are either available as a valid entry, however our focus is on algebraic manipulations and therefore any problems relying on trigonometric identities will not be usable; to convert 20tan(65) to a numeric number, change the 'Options' drop-down list for real values rather than integers

finally, if you wish to change trigonometric values (sin, cos and tan) to/from degrees to radians, then please use Algebrator rather than the web solver (doyourmath.com) [the answer shown assumes '65' is a reference to '65 degrees' rather than radians