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If sin A + cosec A = 2, find the value...

If sin A + cosec A = 2,
find the value of `sin^2 A + "cosec"^2 A`.

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To solve the problem, we need to find the value of \( \sin^2 A + \csc^2 A \) given that \( \sin A + \csc A = 2 \). ### Step-by-Step Solution: 1. **Start with the given equation:** \[ \sin A + \csc A = 2 \] 2. **Substitute \( \csc A \) with \( \frac{1}{\sin A} \):** \[ \sin A + \frac{1}{\sin A} = 2 \] 3. **Multiply both sides by \( \sin A \) to eliminate the fraction:** \[ \sin^2 A + 1 = 2 \sin A \] 4. **Rearrange the equation:** \[ \sin^2 A - 2 \sin A + 1 = 0 \] 5. **Recognize that the left side is a perfect square:** \[ (\sin A - 1)^2 = 0 \] 6. **Solve for \( \sin A \):** \[ \sin A - 1 = 0 \implies \sin A = 1 \] 7. **Find \( \csc A \):** \[ \csc A = \frac{1}{\sin A} = \frac{1}{1} = 1 \] 8. **Now calculate \( \sin^2 A + \csc^2 A \):** \[ \sin^2 A + \csc^2 A = \sin^2 A + \left(\frac{1}{\sin A}\right)^2 \] \[ = 1^2 + 1^2 = 1 + 1 = 2 \] ### Final Answer: \[ \sin^2 A + \csc^2 A = 2 \]
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ICSE-TRIGONOMETRICAL RATIOS -EXERCISE 22(B)
  1. In the given figure, BC=15 cm and sin B = 4/5 . Calculate the measu...

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  2. In the given figure, BC=15 cm and sin B = 4/5 . Now, if tan angleAD...

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  3. If sin A + cosec A = 2, find the value of sin^2 A + "cosec"^2 A.

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  4. If tan A + cot A = 5, find the value of tan^2 A + cot^2 A.

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  5. Given : 4 sintheta = 3 cos theta , find the value of: sin theta

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  6. Given : 4 sintheta = 3 cos theta , find the value of: cos theta

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  7. Given : 4 sintheta = 3 cos theta , find the value of: cot^2 theta ...

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  8. Given : 4 sintheta = 3 cos theta , find the value of: 4 cos^2theta-...

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  9. Given : 17 cos theta = 15, find the value of tan theta + 2 sec theta.

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  10. Given 5 cos A - 12 sin A = 0 , evaluate : (sinA+cosA)/(2 cosA-sinA)

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  11. In the given figure, angleC = 90^@ and D is midpoint of AC. Find : ...

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  12. In the given figure, angleC = 90^@ and D is midpoint of AC. Find : ...

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  13. If 3 cos A = 4 sin A, find the value of : cos A

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  14. If 3 cos A = 4 sin A, find the value of : 3 - cot^2A+ "cosec"^2A

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  15. In triangle ABC, angleB = 90^@ and tan A = 0.75 If AC = 30 cm, find t...

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  16. In rhombus ABCD, diagonals AC and BD intersect each other at point O. ...

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  17. In triangle ABC, AB = AC = 15 cm and BC = 18 cm. Find : cos B

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  18. In triangle ABC, AB = AC = 15 cm and BC = 18 cm. Find : sin C

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  19. In triangle ABC, AB = AC = 15 cm and BC = 18 cm. Find : tan^2B - sec...

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  20. In triangle ABC, AD is perpendicular to BC. sin B = 0.8, BD = 9 cm an...

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