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In any triangle ABC : If a cos A = b co...

In any triangle ABC : If a cos A = b cos B, prove that either the triangle is isosceles or right-angled.

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MODERN PUBLICATION-TRIGNOMETRY-EXERCISE
  1. In any triangle ABC, prove that : (tanC)/(tanA)= (b^2+c^2-a^2)/(a^2+b^...

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  2. In any triangle ABC, prove that : b^2 sin 2C + c^2 sin 2B = 2 bc sin A...

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  3. In any triangle ABC : If a cos A = b cos B, prove that either the tri...

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  4. In any triangle ABC : If sin 2A = sin 2B + sin 2C, prove that either ...

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  5. In Delta ABC, if sin ^(2) A+sin ^(2) B =sin ^(3)C, then the triangle i...

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  6. In any triangle ABC : If (cosA)/a= (cosB)/b, prove that the triangle ...

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  7. Prove that the area of a sector of circle with radius r and central an...

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  8. Prove that the area of a sector of a circle of radius r and an arc of ...

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  9. The greatest angle of a cyclic quadrilateral is three times the least....

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  10. A wire 121 cm long is bent so as to lie along the arc of a circle of 9...

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  11. Prove that: (tan A)/(1-cotA)+ (cotA)/(1-tan A)= 1/ (sinA cosA)+1.

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  12. Prove that (tan^2 theta)/(tan^2 theta-1)+(cosec^2 theta)/ (sec^2 theta...

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  13. Prove that: (tanA+secA-1)/(tan A -secA +1)= secA+tanA.

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  14. Eliminate alpha between the equations: (sin^2 alpha)/(cos alpha)=a^3...

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  15. Find the value of 3(sinx-cosx)^(4)+6(sinx+cos x)^(2)+4(sin^(6)x+cos^(6...

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  16. Given, sin x =-3/7 and x belongs to the third quadrant, obtain the va...

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  17. If 7 sin A = 24 cos A and 0ltAlt pi/2, find 14 tan A - 25 cos A-7 sec...

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  18. If sectheta= x+1/(4x) , then prove that sectheta+tantheta=2x or 1/(2x)...

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  19. If tan theta =p/q, show that : (p sin theta-q cos theta)/(p sin thet...

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  20. If sin x + sin^2 x = 1, show that : cos^4 x+ cos^2 x=1.

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