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In triangle ABC tan(A/2), tan(B/2) and t...

In `triangle ABC` tan(A/2), tan(B/2) and tan (C/2)` are in A.P. then prove that cosA,cosB,cosC are in A.P.

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PATHFINDER-TRIGONOMETRIC FUNCTIONS-QUESTION BANK
  1. for any triangleABC show that (b^2-c^2)/(cosB+cosC)+(c^2-a^2)/(cosC+co...

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  2. if in a triangle ABC ,a^2,b^2,c^2 are in A.P. then show that cotA,cotB...

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  3. In triangle ABC tan(A/2), tan(B/2) and tan (C/2) are in A.P. then prov...

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  4. If in triangleABC ,a^4+b^4+c^4=2c^2(a^2+b^2) then find angleC

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  5. In any triangle ABC if cosA=sinB-cosC then show that any angle of the...

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  6. In any triangle ABC prove that a^2cotA+b^2cotB+c^2cotC=(abc)/R

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  7. in any triangle ABC prove that (b-c)/acos^2(A/2)+(c-a)/(b)cos^2(B/2)+(...

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  8. In triangle ABC if the angles A,B and C be in A.P. then show that 2co...

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  9. In triangle ABC if cosAcosB +sinAsinB sinC=1 then prove that a:b:c=1:1...

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  10. In triangleABC (b+c)/11=(c+a)/12=(a+b)/13 then prove that (cosA)/7=(co...

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  11. in triangleABC if (a^2+b^2)/(a^2-b^2)=sin(A+B)/sin(A-B) then prove th...

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  12. In triangleABC if a/(b+c)=tan(A/2) the show that A+C=pi/2

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  13. if the lengths of sides of a triangle be 1-2x,(x^2-x+1 and (x^2-1) the...

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  14. If in triangleABC ,sin^4A+sin^4B+sin^4C=sin^2Bsin^2C+2sin^2Csin^2A+2si...

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  15. For any triangle ABC prove that acosA+bcosB +c cosC=2a sinBsinC

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  16. If in triangle ABC ,b^2=a(c+a) and c^2=(a+b)b then prove that cosAcos ...

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

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  18. If 8R^2=a^2+b^2+c^2 then show that the triangle is right angled

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  19. If in a triangle ABC ,atanA +btan B =(a+b)tan((A+B)/2) then prove tha...

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

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