Sin(-2π/3)?

1 Answer
May 30, 2018

#-sqrt3/2#

Explanation:

#color(blue)(sin(-(2pi)/3)#

Lets convert it into degrees,
Note:(#pi=180^circ#)

#rarrsin(-(2*180)/3)#

#rarrsin(-(2*cancel180^60)/cancel3^1)#

#rarrsin(-120^circ)#

Now, remember that #color(brown)(sin(-x)=-sin(x)#

So,

#rarrsin(-120^circ)=-sin(120^circ)#

Now lets check out the sin value of #120^circ#

paint

So, #sin(120^circ)=sqrt3/2#

So,

#color(green)(rArrsin(-(2pi)/3)=-sqrt3/2#

Hope that helps!...#phi#