AMO 2022 - Secondary 4 (Grade 10) Question 1

Find $\sin^2 10^\circ+\sin^2 20^\circ+\sin^2 30^\circ+\sin^2 40^\circ+\sin^2 50^\circ+\sin^2 60^\circ+\sin^2 70^\circ+\sin^2 80^\circ$.