Question

In figure OP=3.5cm,QB=1.4cm and angle AOB=120°.find the area of the shaded portion.​

Answer 1

OAB is a sector

O°=120°

OP=3.5cm

QB=1.4cm

so OB=4.9cm or 49/10

Area of shaded region= 120/360πOB² - 120/360πOP²

1/3π(OB²-OP²)

1/3π(4.9-3.5)(4.9+3.5)

1/3π(1.4)(8.4)

=12.32cm²

Hence it's the answer