KVPY2016MathematicsProperties of Triangles
Let AB be a sector of a circle with centre O and radius d, AOB = ( < 2 ) , and D be a point on OA such that BD is perpendicular OA . Let E be the midpoint of BD and F be a point on the arc AB such that EF is parallel to OA . Then the ratio of length of the arc AF to the length of the arc AB is -
Options
- A1 2
- B2
- C1 2
- D⁻¹ ( 1 2 )
Correct answer
D. ⁻¹ ( 1 2 )
Step-by-step solution
CF = r (1- ) EC = r ( - ) CD = r EC + CD = ED r = r 2 = ⁻¹ ( 2 )