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If the incircel of the triangle ABC, thr...

If the incircel of the triangle ABC, through it's circumcentre, then the `cos A + cos B + cos C` is

A

` -2`

B

`sqrt2`

C

`-sqrt2`

D

None of these

Text Solution

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The correct Answer is:
B
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ARIHANT MATHS-PROPERTIES AND SOLUTION OF TRIANGLES -Exercise (Single Option Correct Type Questions)
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  2. In any triangle ABC sum (sin^2A+sinA+1)/sinA is always greater than or...

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  3. If the incircel of the triangle ABC, through it's circumcentre, then t...

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  4. The perimeter of a triangle ABC is six times the arithmetic mean of ...

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  5. If there are only two linear functions f and g which map [1,2] on [4,6...

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  6. A circle is inscribed in an equilateral triangle of side adot The area...

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  7. In any triangle ABC, if sin A , sin B, sin C are in AP, then the maxim...

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  8. In a DeltaABC, 2 cos A=(sin B)/(sin C) and 2 ^(tan^(2)B) is a solution...

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  9. Differentiate the following w.r.t x sin^(-1)(x^(3/2))

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  10. If a,b and c arethe sides of a traiangle such that b.c =lamda ^(2), th...

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  11. Differentiate the following w.r.t x cos(acosx + bsinx) , for som...

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  12. In triangle ABC, a=5, b=4 and cos(A+B)=(31)/(32) In this triangle,c=

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  13. In a A B C ,ifA B=x , B C=x+1,/C=pi/3 , then the least integer value ...

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  14. In an equilateral triangle, three coins of radii 1 unit each are kept ...

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  15. Differentiate the following w.r.t x 2x^((x^4-3))

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  16. Differentiate the following w.r.t x x^x + a^a

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  17. In a triangle ABC , the line joining the circumcentre and incentre is ...

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  18. In the given figure, AB is the diameter of the circle, centered at O. ...

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  19. In a triangle ABC, AD, BE and CF are the altitudes and R is the circum...

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  20. Find dy/dx , If x = a(sint - t cost) and y = a(cost + t sint)

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