Correct Answer - C
Graphically:
`/_ROQ=theta//2, /_RQO=theta//2`
Hence, `DeltaOQR` is isosceles.
`rArr OR= RQrArr B=A`
Analytically:
`tan(theta//2) =(Bsin theta)/(A+B cos theta)`
`rArr (sin(theta//2))/(cos(theta//2))=(2Bsin(theta//2) cos(theta//2))/(A+B[2cos^(2)(theta//2)-1])` ltbr `rArr A+2 Bcos^(2)(theta//2)-B=2B cos^(2)(theta//2)rArr A=B`
` rArr A+2B cos^(2)(theta//2)-B=2B cos^(2)(theta//2) rArr A=B`