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In a DeltaABC the angles A, B, C are in ...

In a `DeltaABC` the angles A, B, C are in A.P. show that `2cos""(A-C)/2=(a+c)/sqrt((a^(2)-ac+c^(2)))`

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VMC MODULES ENGLISH-PROPERTIES OF TRIANGLE-JEE Advanced (Archive)
  1. In a DeltaABC the angles A, B, C are in A.P. show that 2cos""(A-C)/2=(...

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  2. If the angles A, B and C of a triangle are in an arithmetic progressio...

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  3. In a Delta ABC, among the following which one is ture ?

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  4. The side of a triangle are in the ratio 1 : sqrt3:2, then the angles o...

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  5. If the angles of a triangle are in the ratio 4:1:1, then the ratio of ...

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  6. In a triangle ABC, 2 ac sin (1/2(A-B + C)) =

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  7. In a triangle PQR, ∠R=π/2.If tan(P/2) & tan(Q/2), are the roots of the...

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  8. If in a triangle PQR; sin P, sin Q, sin R are in A.P; then (A)the alt...

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  9. In a DeltaABC, angleB=(pi)/(3) and angleC=(pi)/(4) let D divide BC in...

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  10. Let A B C be a triangle such that /A C B=pi/6 and let a , b and c deno...

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  11. Let PQR be a triangle of area Delta with a = 2, b = 7//2, and c = 5//2...

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  12. One angle of an isosceles triangle is 120^0 and the radius of its incr...

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  13. In a triangle, the sum of two sides is x and the product of the same t...

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  14. Which of the following pieces of data does NOT uniquely determine an ...

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  15. In triangle ABC, let angle C = pi//2. If r is the inradius and R is ci...

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  16. Consider the circle x^2 + y^2 = 9 and the parabola y^2 = 8x. They inte...

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  17. Consider the circle x^2 + y^2 = 9 and the parabola y^2 = 8x. They inte...

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  18. Consider the circle x^2 + y^2 = 9 and the parabola y^2 = 8x. They inte...

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  19. about to only mathematics

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  20. A triangle A B C with fixed base B C , the vertex A moves such that co...

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  21. Internal bisector of angle A of Delta ABC meets side BC to D. A line ...

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