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In triangle A B C , prove that cos e c ...

In triangle ` A B C ,` prove that `cos e c A/2+cos e c B/2+cos e c C/2geq6.`

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CENGAGE PUBLICATION-TRIGONOMETRIC FUNCTIONS-All Questions
  1. The exradii r1,r2 and r3 of /\A B C are in H.P. Show that its sides a...

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  2. Find the number of roots of the equation tan(x+pi/6)=2tanx ,forx in (0...

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  3. In triangle A B C , prove that cos e c A/2+cos e c B/2+cos e c C/2geq...

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  4. If x=(2sintheta)/(1+costheta+sintheta),t h e n(1-costheta+sintheta)/(1...

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  5. C F is the internal bisector of angle C of A B C , then C F is equal ...

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  6. Solve the equation 2(cos x+cos2x)+sin2x(1+2cos x)=2sinx for (-pilt=xlt...

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  7. Which of the following is not the quadratic equation whose roots are c...

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  8. If A+B+C=pi, prove that (tanA)/(tanBdottanC)+(tanB)/(tanAdott a n C...

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  9. In triangle ABC, line joining the circumcenter and orthocenter is para...

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  10. Solve 8sinx=(sqrt(3))/(cosx)+1/(sinx)

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  11. If cos e ctheta-cottheta=q , then the value of cos e ctheta is

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  12. If A+B+C=pi , prove that cotA+cotB+cotC-cos e cAdotcos e cBdotcos e cC...

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  13. Let D be the middle point of the side B C of a triangle A B Cdot If th...

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  14. Solve 2tantheta-cottheta=-1

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  15. If sec^4theta+sec^2theta=10+tan^4theta+tan^2theta, then sin^2theta=

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  16. If cos(A+B+C)=cosAcosBcosC , then find the value of (8sin(B+C)sin(C+A)...

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  17. In the given figure, what is the radius of the inscribed circle? 3/2 ...

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  18. Solve tan3theta=-1

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  19. If sinA=sin^2Ba n d2cos^2A=3cos^2B then the triangle A B C is right...

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  20. In triangle A B C , if cotA *cotC=1/2a n dcot B* cotC=1/(18), then t...

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