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Find value of sin (- 13 pi/3)

Question:

Find the value of sin (- 13pi/3)

Solution:

using formula: sin (- x) = - sin x

sin (- 13pi/3) = - sin (13pi/3)

13pi/3 = 4pi + pi/3 = 2pi × 2 + pi/3

sin (- 13pi/3) = - sin (13pi/3) = - sin (2pi × 2 + pi/3)

using formula: sin (2pi × k + x) = sin x, k is an integer

sin (- 13pi/3)
= - sin (13pi/3)
= - sin (2pi × 2 + pi/3)
= - sin (pi/3)
= - sin 60o
= - Sqrt (3)/2

Therefore, sin (- 13 pi/3) = - Sqrt (3)/2. Watch the video for more details.

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