What is the exact value of sin(-2pi/3)

opposite side       -√3

= = sin -2π/3

hypotenuse            2

Step-by-step explanation:

Note that +π/3 radians corresponds to +60°, and so +2π/3 radians corresponds to +120°.  Similarly,  -π/3 radians corresponds to -60°, and so -2π/3 radians corresponds to -120°.  

-2π/3 radians is in Quadrant III.  The "opposide" (the side opposite the angle) has length √3 when the radius of the circle is 2; because this angle is in Q III, we give it the - sign:  -√3.

Thus, the sine of -2π/3 is:

opposite side       -√3

= = sin -2π/3

hypotenuse            2

y/x=18

step-by-step explanation:

it would take 7/10 of an hour too fill the pool.

step-by-step explanation: