Question

Хелп,19 баллов
Sin^2(arccos4/5)

Answer 1

$sin(arccosx)= \sqrt{1-x^2} \\ sin^2(arccos(4/5))= \sqrt{1- \frac{16}{25} }= (\frac{3}{5})^2 \\ sin^2(arccos(4/5))= \frac{9}{25}$