Как нарисовать графики функций y= 4cosx-1 и y=sin(x+П/3)

Дан параллелограмм АВСD
Координаты точек:А(3;-7),С(-5;-1),точка О-пересечение диагоналей 
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перевести текст:Rock and roll began in the 1950s in America. Some of its first starts were black. They brought traditional rhythm and blues to people. Then white singers appeared and the most popular of them was Elvis Presley.