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If in a DeltaABC , a^2cos^2A=b^2+c^2, th...

If in a `DeltaABC , a^2cos^2A=b^2+c^2,` then

A

`Altpi/4`

B

`pi/4ltAltpi/2`

C

`Agtpi/2`

D

`A=pi/2`

Text Solution

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The correct Answer is:
C
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PATHFINDER-SOLUTION OF TRIANGLE AND HEIGHT AND DISTANCE-QUESTION BANK
  1. If in a triangle (1-r1/r2)(1-r1/r3)=2,then the triangle is

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  2. If I is the incenter of DeltaABC, then the ratio IA:IB:IC is equal t...

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  3. If in a DeltaABC , a^2cos^2A=b^2+c^2, then

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  4. In any DeltaABC, prod(sin^2A+sinA+1)/sinA is always greater than

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  5. In any triangle ABC,sum(sin^2A+sinA+1)/sinAis always greater than

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  6. In DeltaABC, the value of ((r1+r2)(r2+r3)(r3+r1))/(R(s)^(2) is

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  7. If in a triangle (s-a)/11=(s-b)/12=(s-c)/13, then tan^2(A/2)

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  8. If in a triangle ABC, angleB=60^@,then

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  9. Given an isosceles triangle with equal sides of length b,base angle a...

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  10. In DeltaABC,A=15^@,b =10sqrt2cm the value of 'a' for which these will ...

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  11. In DeltaABC, a=5,b=4,A=(pi/2)+B, thenC

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  12. If tanA, tanB are the roots of the quadratic abx^2-c^2x+ab=0, where a,...

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  13. There exist a triangle ABC satisfying

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  14. In a DeltaABC,tanClt 0. Then

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  15. If the since of the angles A and B of a triangle ABCsatisfy the equati...

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  16. In a DeltaABC tanA and tanB satisfy the equation sqrt3x^2-4x+sqrt3lt0...

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  17. For a triangle ABC, which of the following is true?

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  18. ABCD be a cycle quadrilateral inscribed in a circle of radius R. T...

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  19. A quadrilateral ABCD is such that one circle can be inscribed in it an...

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  20. ABCD be a cyclic quadrilateral inscribed in a circle of radius R. In p...

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