The straight line y=kx+ 1 intersects the circle x 2+y 2 =1at two points p and q,
Angle POQ= 120 degrees.
Then the distance from O to PQ is d= 1/2.
According to the distance formula from point to straight line
1/√(k? + 1)= 1/2
∴k? =3,
∴k= √3