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Solve the general value. 2 + sqrt3 sec...

Solve the general value.
`2 + sqrt3 sec x - 4 cos x = 2 sqrt3`

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To solve the equation \( 2 + \sqrt{3} \sec x - 4 \cos x = 2 \sqrt{3} \), we will follow these steps: ### Step 1: Rewrite the equation Start with the given equation: \[ 2 + \sqrt{3} \sec x - 4 \cos x = 2 \sqrt{3} \] ### Step 2: Multiply through by \( \cos x \) To eliminate the secant function, multiply the entire equation by \( \cos x \): \[ (2 + \sqrt{3} \sec x - 4 \cos x) \cos x = (2 \sqrt{3}) \cos x \] This simplifies to: \[ 2 \cos x + \sqrt{3} - 4 \cos^2 x = 2 \sqrt{3} \cos x \] ### Step 3: Rearrange the equation Rearranging gives: \[ -4 \cos^2 x + 2 \cos x - 2 \sqrt{3} \cos x + \sqrt{3} = 0 \] Combine like terms: \[ -4 \cos^2 x + (2 - 2\sqrt{3}) \cos x + \sqrt{3} = 0 \] ### Step 4: Multiply by -1 To make the leading coefficient positive, multiply the entire equation by -1: \[ 4 \cos^2 x - (2 - 2\sqrt{3}) \cos x - \sqrt{3} = 0 \] ### Step 5: Use the quadratic formula This is a quadratic equation in the form \( ax^2 + bx + c = 0 \) where: - \( a = 4 \) - \( b = -(2 - 2\sqrt{3}) \) - \( c = -\sqrt{3} \) Using the quadratic formula \( \cos x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \): \[ b^2 = (2 - 2\sqrt{3})^2 = 4 - 8\sqrt{3} + 12 = 16 - 8\sqrt{3} \] \[ 4ac = 4 \cdot 4 \cdot (-\sqrt{3}) = -16\sqrt{3} \] Thus, \[ b^2 - 4ac = (16 - 8\sqrt{3}) - (-16\sqrt{3}) = 16 - 8\sqrt{3} + 16\sqrt{3} = 16 + 8\sqrt{3} \] Now substituting into the quadratic formula: \[ \cos x = \frac{2 - 2\sqrt{3} \pm \sqrt{16 + 8\sqrt{3}}}{8} \] ### Step 6: Solve for \( \cos x \) Calculate the values of \( \cos x \): 1. For \( \cos x = \frac{2 - 2\sqrt{3} + \sqrt{16 + 8\sqrt{3}}}{8} \) 2. For \( \cos x = \frac{2 - 2\sqrt{3} - \sqrt{16 + 8\sqrt{3}}}{8} \) ### Step 7: Find angles corresponding to \( \cos x \) 1. If \( \cos x = \frac{1}{2} \), then \( x = \frac{\pi}{3} + 2n\pi \) or \( x = -\frac{\pi}{3} + 2n\pi \). 2. If \( \cos x = -\frac{\sqrt{3}}{2} \), then \( x = \frac{5\pi}{6} + 2n\pi \) or \( x = -\frac{5\pi}{6} + 2n\pi \). ### Step 8: Write the general solution The general solutions are: \[ x = 2n\pi \pm \frac{\pi}{3}, \quad n \in \mathbb{Z} \] \[ x = 2n\pi \pm \frac{5\pi}{6}, \quad n \in \mathbb{Z} \] ### Final Answer Thus, the general solution for the equation \( 2 + \sqrt{3} \sec x - 4 \cos x = 2 \sqrt{3} \) is: \[ x = 2n\pi \pm \frac{\pi}{3}, \quad n \in \mathbb{Z} \] \[ x = 2n\pi \pm \frac{5\pi}{6}, \quad n \in \mathbb{Z} \]
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ICSE-TRIGONOMETRIC EQUATIONS -EXERCISE 6
  1. Solve the general vlaue. 2cos ^(2) theta - 5 cos theta + 2 = 0

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  2. Solve the general vlaue. 2 sin ^(2) x + sqrt3 cos x + 1 =0

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  3. Solve the general value. 2 + sqrt3 sec x - 4 cos x = 2 sqrt3

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  4. Solve the general value. tan ^(2) theta - (1 + sqrt3) tan theta + sq...

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  5. Solve the general vlaue. tan theta + 4 cot 2 theta + 1=0

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  6. Solve the general vlaue. tan theta + tan 2 theta + sqrt3 tan theta t...

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  7. Solve the general vlaue. cot theta + tan theta = 2 cosec theta

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  8. Solve the general vlaue. 2 cos theta + cos 3 theta =0

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  9. Solve the general vlaue. 2 sin 2 x - sin x =0

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  10. Solve the general vlaue. tan 2x + 2 tan x =0

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  11. Solve the general vlaue. sin 7 theta + sin 4 theta + sin theta =0

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  12. Solve the general vlaue. cos theta + cos 2 theta + cos 3 theta =0

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  13. Solve the general vlaue. sin theta + cos theta = sqrt2

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  14. Solve the general vlaue. sin theta + sqrt3 cos theta = sqrt2

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  15. Solve the general vlaue. sqrt2 sec theta + tan theta =1

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  16. Solve the general vlaue. 3-2cos theta -4sin theta - cos 2 theta + si...

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  17. If the equation a cos 2 theta +b sin 2 theta = c had theta (1), the...

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  18. If alpha , beta are two different values of theta lying between 0...

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  19. Find all the values of theta satisfying the equation cos 2 theta - c...

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  20. Find the general value of theta in sec theta - cosec theta = (4)/(3)

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