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Bisectors of angles A, B and C of a tri...

Bisectors of angles A, B and C of a triangle ABC intersect its circumcircle at D, E and F respectively. Prove that the angles of the triangle DEF are `90^@-1/2A`,`90^@-1/2B` and `90^@-1/2C`

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RD SHARMA ENGLISH-CIRCLE -All Questions
  1. D is a point on the circumcircle of A B C in which A B=A C such tha...

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  2. The bisector of /B of an isosceles triangle A B C with A B=A C mee...

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  3. Bisectors of angles A, B and C of a triangle ABC intersect its circum...

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  4. Prove that the mid-point of the hypotenuse of a right triangle is eq...

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  5. A B is a diameter of a circle with centre O and radius O D is perp...

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  6. In Figure, P , is any point on the chord B C of a circle such that A B...

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  7. In Figure, AB is a diameter of the circle, CD is a chord equal to th...

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  8. In Figure, O is the centre of the circle. If /A P B=50^0, find /A O B\...

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  9. In Figure, it is given that O is the centre of the circle and /A O...

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  10. In Figure, O is the centre of the circle. Find /B A C

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  11. If O is the center of the circle, find the value of x in each of t...

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  12. If O is the circumcentre of /\ A B C and O D|B C , prove that /B O D=...

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  13. In the figure, O is the center of the circle and BO is the bisector of...

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  14. In Figure, O is the centre of the circle, prove that /x=/y+/z

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  15. In Figure, O\ a n d\ O ' are centres of two circles intersecting at ...

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  16. In Figure, O is the centre of a circle and P Q is a diameter. If /R...

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  17. In Figure, if /A C B=40^@,\ /D P B=120^@,\ find /C B D

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  18. A chord of a circle is equal to the radius of the circle. Find the ...

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  19. In Figure, P Q R S is a cyclic quadrilateral. Find the measure of each...

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  20. In Figure, if /D B C=70^@\ a n d\ /B A C=30^@,\ find /B C D. Furthe...

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