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If (sinA)/3=(sin B)/3=(sin C)/4 then pro...

If (sinA)/3=(sin B)/3=(sin C)/4 then prove that cosC=1/9

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If (sin A)/3 = (sin B)/3 = (sin C)/4 , then prove that, cos C=1/9 .

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PATHFINDER-TRIGONOMETRIC FUNCTIONS-QUESTION BANK
  1. If in triangleABC a=3cm,b=5cm and angle C=120^@ then c=

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  2. If 2cosA=sinB/sinC then show that the triangle is an isosceles triangl...

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  3. If (sinA)/3=(sin B)/3=(sin C)/4 then prove that cosC=1/9

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  4. The lengths of sides of triangle ABC are a units, b units and sqrt(a^2...

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  5. For any triangleABC show that c^2(sin^2B-sin^2A)+b^2(sin^2A-sin^2C)+a^...

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  6. Prove that for a triangle ABC, (a^2-b^2-c^2) tan A+(a^2-b^2+c^2)tan B=...

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  7. In any triangle ABC prove that sin2A+sin2B+sin2C=(abc)/(2R^3)

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  8. If (a+b+c)(b+c-a)=3bc then show that angleA=pi/3

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  9. If the angles of the triangle ABC are in A.P. and b:c=sqrt3:sqrt2 then...

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  10. For triangleABC prove that (sin A+sin B)(sin B+sin C)(sin C+sin A)gtsi...

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  11. If in triangleABC, (2cosA)/a+(cosB)/b+(2cosC)/c=a/(bc)+b/(ca) then de...

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  12. If sin A/sin C=sin(A-B)/sin(B-C) then show that a^2,b^2,c^2 are in ari...

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  13. a,b,c are the lengths of sides of triangleABC and 1/(a+c)+1/(b+c)=3/(a...

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  14. In triangleABC show that a=bcosC+ccosB

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  15. In triangleABC if angleA=60^@ then show that (b+c)/a=2cos((B-C)/2)

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  16. For any triangle ABC show that a sin(B-C)+bsin(C-A)+csin(A-B)=0

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  17. In triangleABC angleC=90^@ then show that (a^2+b^2)/(a^2-b^2)sin(A-B)...

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  18. In triangleABC if acos^2(C/2)+c cos^2(A/2)=3b/2 then show that a,b,c a...

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  19. In any triangle ABC show that b^2sin2C+c^2sin 2B=abc/R

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  20. In any triangle ABC show that sinA+sinB gt sin C

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