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Let 'l' is the length of median from the...

Let 'l' is the length of median from the vertex A to the side BC of a `Delta ABC`. Then

A

`4l^2=b^2 4 ac cos B`

B

`4l^2 = a^2 +4 bc cos A`

C

`4l^2= c^2+4ab cos C`

D

`4l^2 = b^2 2c^2-2a^2`

Text Solution

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The correct Answer is:
B
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MOTION-SOLUTION OF TRIANGLE-EXERCISE - 2 (LEVEL I)
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  2. cot (A+B)/2.tan(A-B)/2= (a) (a+b)/(a-b) (b) (a-b)/(a+b)

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  3. In any triangle ABC,1-tan(A/2)tan(B/2)=

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  4. In a triangleABC, if 3tan (A/2) tan (C /2)=1, then sides a,b,c are in

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  5. If, in Delta ABC, a = 16, b = 24, c = 20, then : sin (A/2)= ....

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  6. In triangleABC, (b+a-c)tan((A)/(2))=

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  7. If, in Delta ABC, a = 2x, b = 2y and C = 120^(@) then the area of the ...

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  8. If the median AD of triangle ABC divides the angle BAC in the ratio 1:...

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  9. In a triangle ABC , let angleC=(pi)/2. If r is the in-radius and R is ...

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  10. In an isosceles triangle with base angle alpha and lateral side 4, Rr=

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  11. If I is the incentre of a triangle whose is radius and circumradius ar...

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  12. AD, BE and CF are the medians of triangle ABC whose centroid is G. If ...

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  13. Let 'l' is the length of median from the vertex A to the side BC of a ...

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  14. If in a /\ ABC the altitude from the vertices A,B,C on opposite side a...

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  15. If the radius of the circum-circle of an isosceles triangle PQR is equ...

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  16. In a triangle ABC, if a=2,b=4,c=5 then cosA=

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  17. If in a triangle ABC a,b,c are roots of the equation x^3 - 11 x^2 + 38...

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  18. In a triangle A+B+C=90 then prove that cotA+cotB+cotC=cotAcotBcotC

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  19. If cos A=(sinB)/(2 sin C), then triangleABC is

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  20. Let A, B and C are the angles of a plain triangle and tan(A/2)=1/3...

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