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For a DeltaABc, it is given that cosA +c...

For a `DeltaABc,` it is given that cosA +cosB+cosC=3/2. prove that the `Delta` is equilateral.

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PATHFINDER-SOLUTION OF TRIANGLE AND HEIGHT AND DISTANCE-QUESTION BANK
  1. In a DeltaABC prove that: a^3cos(B-C)+b^3cos(C-A)+c^3cos(A-B)=3abc

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  2. In triangle ABC, D is the mid point of side BC. If AD is perpendicular...

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  3. For a DeltaABc, it is given that cosA +cosB+cosC=3/2. prove that the D...

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  4. If any DeltaABC, show that : (sin^2A+sinA+1)/sinAge3

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  5. In a DeltaABC, if cotA+cosB+cotC=sqrt3. prove that the Deltais equilat...

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  6. Perpendiculars are drawn from the anglesA, B,C,of an acute angles Delt...

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  7. ABCD is a trapezium such that AB,DC.are parallel and BC is perpendicul...

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  8. For any triangle ABC, ((a+b+c)(b+c-a)(c+a-b)(a+b-c))/(4b^2c^2)is equa...

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  9. In DeltaABC, if a =5,b=4 and cos (A-B)=31/32,then the perimeter of tr...

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  10. If in triangle ABC,cot(A/2)=(b+c)/a, then the triangleABC is

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  11. In a triangleABC, tan(A/2)=5/6,tan(C/2)=2/5. Then which of the followi...

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  12. In a triangle ABC , c^2=a^2+b^2 ,2s=a+b+c. Then 4s(s-a)(s-b)(s-c)is e...

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  13. In a triangle ABC, acosA=bcosB. Then the triangle is

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  14. Sides of a triangle ABC are in A.P. If a lt min{b,c},then cosA may be ...

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  15. Angles A, Band C of a triangle ABC are in A.P.If b/c=sqrt3/sqrt2, then...

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  16. In a triangleABC, bccotA+cacotB+c abcotC is equal to ?

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  17. In a triangle ABC, (acosA+bcosB+ccc cosC)/(a+b+c) is equal to

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  18. In a triangle ABC, angleB = pi/3 and angleC= pi/4. Let D divide side B...

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  19. If in a triangle ABC,(2cosA)/a+(cosB)/b+(2cosC)/c=a/(bc)+b/(ac), then ...

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  20. If the bisector of angle A of triangle ABC makes an angle theta with ...

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