How to evaluate value of sin (300)+tan(210)?

How to evaluate value of sin (300^circ)+tan(210^circ) ?

1 Answer
May 11, 2018

sin300^circ+tan210^circ=-1/(2sqrt3)~~-0.2887

Explanation:

Here,

sin300^circ=sin(360^circ-60^circ)...toIV^(th)Quadrant

color(white)(sin300^circ)=-sin60^circ...tosin < 0

color(white)(sin300^circ)=-sqrt3/2

We have,

tan210^circ=tan(180^circ+30^circ)...toIII^(rd)Quadrant

color(white)(tan210^circ)=tan30^circ...totan > 0

color(white)(tan210^circ)=1/sqrt3

So,

sin300^circ+tan210^circ=-sqrt3/2+1/sqrt3=-(sqrt3/2-1/sqrt3)

sin300^circ+tan210^circ=-(3- 2)/(2sqrt3)=-1/(2sqrt3)~~-0.2887