If the chord y=mx+1 of the circles x2+y2=1 subtends an angle of 45° at the major segment of the circle, then the value of m is

The given circle isx2+y2=1C≡(0,0), radius =1and chord is. y=mx+1cos⁡45∘=CPCRPerpendicular distance from(0, 0) to the chord y = mx +1,CP=1m2+1, (CR= Radius =1)or cos⁡45∘=1/m2+11or 12=1m2+1or m2+1=2or m=±1