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If in triangle ABC cosA+cosB+cosC=3/2 th...

If in `triangle ABC` cosA+cosB+cosC=3/2 then prove that triangle is equilateral

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PATHFINDER-TRIGONOMETRIC RATIOS AND IDENTITIES-QUESTION BANK
  1. show that (sinx)/(cos3x)+(sin3x)/(cos9x)+(sin9x)/(cos27x)=1/2(tan27x-t...

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  2. If in a triangle ABC cot(A/2)+cot(C/2)=2cot(B/2) then find the minimum...

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  3. If in triangle ABC cosA+cosB+cosC=3/2 then prove that triangle is equi...

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  4. If tan(alpha/2)=sqrt((a-b)/(a+b)) tan(beta/2) prove that cosalpha=(aco...

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  5. If tanalpha=1/7 ,sinbeta=1/sqrt10 prove that alpha+2beta=(pi/4) where ...

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  6. Show that 2^(sinx)+2^(cosx)ge2^(1-(1/sqrt2))

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  7. (sin(-660^@)tan(1050^@).sec(420^@))/(cos(225^@)cosec(315^@)cos(510^@))...

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  8. If A+B+C=180^@ and tanA +tan B+tan Cgek where A,B,C are acute angles t...

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  9. The value of sin theta and tan theta if cos theta=(-12/13) and theta l...

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  10. The expression 3{sin^4((3pi/2)-alpha)+sin^4(3pi-alpha)} -2{sin^6(pi/2+...

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  11. cos 510^@cos330^@+sin 390^@cos120^@=

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  12. If ABCD is a cyclic quadrilateral then the value of cosA+cosB+cos C+co...

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  13. If (secA-tan A)(secB -tan B)(sec C-tan C)(sec A+tan A)(sec B+tan B)(se...

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  14. The value of the expression 1-sin^2y/(1+cosy)+(1+cosy)/siny-siny/(1-co...

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  15. sin^2A+sin^2(A-B)+2sinAcosBsin(B-A) is equal to

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  16. Let A and B denote the statements A:cos alpha+cos beta+cos gamma=0,B:s...

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  17. If tan beta=(nsin alphacosbeta)/(1-ncos^2alpha) then tan(alpha+beta) i...

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  18. The value of sin20^@sin 40^@sin 60^@sin 80^@ is

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  19. In a triangle ABC,sin A-cos B=cosC,then angle B is

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  20. If Un=2 cosntheta then U1Un-U(n-1) is equal to

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