Как решить? Y=2 sin(x/2-П/4)

1 The foundation of the Russian capital and some facts from its history.2 Red Square is the heart of Moscow.3 Masterpieces of Red Square and the Kremlin.4 Places of interest in Moscow.5 Moscow is a city of museums.6 The Bolshoi Opera House is the best-known theatre.7 Moscow is the centre of political life of the country.

2sin(x/2-π/4)=2·(sinx/2·cosπ/4-sinπ/4·cosx/2)=2·(sinx/2·√2/2-√2/2·cosx/2)=2·√2/2·(sinx/2-cosx/2)=√2(sinx/2-cosx/2)