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Prove m:n theorem in a Delta ABC, a poin...

Prove m:n theorem in a `Delta ABC`, a point D is taken on side BC such that BD:DC is m:n. Then prove that(1)`(m+n)cottheta= mcotalpha -ncotbeta` (2) `(m+n)cottheta= ncotB-mcotC`

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Note This is known as m-n thereom.
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ARIHANT MATHS-PROPERTIES AND SOLUTION OF TRIANGLES -Exercise (Questions Asked In Previous 13 Years Exam)
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  10. Let A B Ca n dA B C ' be two non-congruent triangles with sides A B=4,...

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

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

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  15. Internal bisector of /A of triangle ABC meets side BC at D. A line dra...

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

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  17. In Delta ABC, which one is true among the following ?

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  20. For a regular polygon, let r and R be the radii of the inscribed and t...

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  21. In triangle A B C , let /c=pi/2dot If r is the inradius and R is circu...

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