IIT JEE 2009 P1 Q32

In a triangle ABC with fixed base BC, the vertex A moves such that cos B + cos C = 4 sin²(A/2)

If a,b,c denote the lengths of the sides of the triangle opposite to the angles A,B and C respectively, then

A) b+c=4a
B) b+c=2a
C) locus of point A is an ellipse
D) locus of point A is a pair of straight lines..

1 Answers

[url=http://iitjee2009solutions.targetiit.com]Solution Key with Question Paper of 2009 IIT JEE[/url]

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