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Find six angles for which sin theta=-(sq...

Find six angles for which `sin theta=-(sqrt(3))/(2)`.

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To find six angles for which \( \sin \theta = -\frac{\sqrt{3}}{2} \), we can follow these steps: ### Step 1: Identify the reference angle The sine function is negative in the third and fourth quadrants. The reference angle for \( \sin \theta = \frac{\sqrt{3}}{2} \) is \( \frac{\pi}{3} \). ### Step 2: Determine the angles in the third and fourth quadrants 1. In the third quadrant, the angle can be calculated as: \[ \theta = \pi + \frac{\pi}{3} = \frac{4\pi}{3} \] 2. In the fourth quadrant, the angle can be calculated as: \[ \theta = 2\pi - \frac{\pi}{3} = \frac{5\pi}{3} \] ### Step 3: General solution for sine function The general solution for \( \sin \theta = \sin \alpha \) is given by: \[ \theta = n\pi + (-1)^n \alpha \] where \( n \) is any integer and \( \alpha \) is the reference angle. ### Step 4: Apply the general solution Here, \( \alpha = -\frac{\pi}{3} \). Therefore, we can write: \[ \theta = n\pi + (-1)^n \left(-\frac{\pi}{3}\right) \] ### Step 5: Calculate specific angles for different values of \( n \) 1. For \( n = 0 \): \[ \theta = 0 + (-1)^0 \left(-\frac{\pi}{3}\right) = -\frac{\pi}{3} \] 2. For \( n = 1 \): \[ \theta = \pi + (-1)^1 \left(-\frac{\pi}{3}\right) = \pi + \frac{\pi}{3} = \frac{4\pi}{3} \] 3. For \( n = 2 \): \[ \theta = 2\pi + (-1)^2 \left(-\frac{\pi}{3}\right) = 2\pi - \frac{\pi}{3} = \frac{5\pi}{3} \] 4. For \( n = 3 \): \[ \theta = 3\pi + (-1)^3 \left(-\frac{\pi}{3}\right) = 3\pi + \frac{\pi}{3} = \frac{10\pi}{3} \] 5. For \( n = -1 \): \[ \theta = -\pi + (-1)^{-1} \left(-\frac{\pi}{3}\right) = -\pi + \frac{\pi}{3} = -\frac{2\pi}{3} \] 6. For \( n = -2 \): \[ \theta = -2\pi + (-1)^{-2} \left(-\frac{\pi}{3}\right) = -2\pi - \frac{\pi}{3} = -\frac{7\pi}{3} \] ### Final angles The six angles for which \( \sin \theta = -\frac{\sqrt{3}}{2} \) are: 1. \( -\frac{\pi}{3} \) 2. \( \frac{4\pi}{3} \) 3. \( \frac{5\pi}{3} \) 4. \( \frac{10\pi}{3} \) 5. \( -\frac{2\pi}{3} \) 6. \( -\frac{7\pi}{3} \)
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ICSE-TRIGONOMETRICAL FUNCTIONS -Exercise 4(d)
  1. Find the values of theta lying between 0^(@) and 360^(@) when tan th...

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  2. Find the values of theta lying between 0^(@) and 360^(@) when sec th...

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  3. Find the values of theta lying between 0^(@) and 360^(@) when sin th...

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  4. Find the values of theta lying between 0^(@) and 360^(@) when tan th...

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  5. Find the values of theta lying between 0^(@) and 360^(@) when sin th...

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  6. Find the values of theta lying between 0^(@) and 360^(@) when costhe...

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  7. If 0^(@)lt theta lt 90^(@) and cos theta=(4)/(5) find the values of ...

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  8. If 0^(@)lt theta lt 90^(@) and cos theta=(4)/(5) find the values of ...

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  9. If 0^(@)lt theta lt 90^(@) and cos theta=(4)/(5) find the values of ...

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  10. If 0^(@)lt theta lt 90^(@) and cos theta=(4)/(5) find the values of ...

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  11. Find six angles for which sin theta=-(sqrt(3))/(2).

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  12. Find all the angles between 0^(@) and 720^(@) whose tangent is -(1)/(s...

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  13. Find the values of theta between 0^(@) and 360^(@) which satisfy the e...

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  14. Find the values of theta between 0^(@) and 360^(@) which satisfy the e...

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  15. If tan theta=0.4, when theta lies between 0^(@) and 360^(@), write dow...

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  16. If cosx^(@)=sin 200^(@), find the possible values of x between -180^(@...

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  17. If A,B,C are angles of a triangle, prove that cosC=-cos(A+B).

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  18. If A,B,C are angles of a triangle, prove that "tan "(B+C)/(2)="cot"...

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  19. If A,B,C are angles of a triangle, prove that (tan (B+C)+tan(C+A)+ta...

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  20. If A,B,C,D are the angles of a quadrilateral, prove that "cos"1/2(A+B)...

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