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In Delta ABC, if 4r=3R then cos A+ cos B...

In `Delta ABC, if 4r=3R` then cos A+ cos B+ cos C=

A

`1//4`

B

`3//4`

C

`5//4`

D

`7//4`

Text Solution

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The correct Answer is:
D
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DIPTI PUBLICATION ( AP EAMET)-PROPERTIES OF TRIANGLES -EXERCISE 1B
  1. In Delta ABC, if r1,r2,r3 are in H.P., then r2//r=

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  2. In Delta ABC, if r1=r2=r3 then the triangle is

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  3. In Delta ABC, if r r1=r2 r3, then the triangle is

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  4. In Delta ABC the roots of the equation x^3-(r+4R)x^2+s^2x-s^2r=0 are

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  5. In Delta ABC, if r1 lt r2 lt r3 then

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  6. In Delta ABC, if 2r1=3r2=r3, then a:b:c=

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  7. In Delta ABC, if 4r=3R then cos A+ cos B+ cos C=

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  8. In Delta ABC is H is the orthocentre of Delta ABC and x= AH, y=BH, z=C...

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  9. If the line joining the circumcentre 'O' and the incentre I is paralle...

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  10. In Delta ABC, if 2R+r=r1 then the triangle is

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  11. If A,A(1),A(2),A(3) are the areas of incircle and ex-circle of a trian...

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  12. The ratio of the area of the incircle to the area of Delta ABC is

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  13. If p(1),p(2),p(3) are altitudes of a DeltaABC then show that (1)/(...

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  14. IF p1,p2,p3 are the lengths of the altitudes of a triangle from the ve...

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  15. IF p1,p2,p3 are the lengths of the altitudes of a triangle from the ve...

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  16. IF p1,p2,p3 are the lengths of the altitudes of a triangle from the ve...

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  17. IF p1,p2,p3 are the lengths of the altitudes from the vertices of Delt...

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  18. IF p1,p2,p3 are the lengths of the altitudes from the vertices of Delt...

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  19. If in a triangle ABC, the altitudes from the A,B,C on opposite sides a...

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  20. If Delta ABC, A' B' C' are such that B=B', A+A'=180^@, then aa'=

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