Question Number 133950 by liberty last updated on 25/Feb/21
$$\mathrm{Find}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\: \\ $$$$\mathrm{sin}\:^{\mathrm{2}} \left(\frac{\mathrm{9}\pi}{\mathrm{10}}\right).\mathrm{sin}\:^{\mathrm{2}} \left(\frac{\mathrm{7}\pi}{\mathrm{10}}\right). \\ $$
Answered by bobhans last updated on 25/Feb/21
