Lengths of segments in a circle

[size=150][size=200]Lengths of the segments (parts) of a tangent segment and a secant segment are drawn to a circle from an external point.[/size][/size]
[size=150][size=200]Pay attention to the value ОА∙ОВ and ОС^2 in the Table.[/size][/size]

Information: Lengths of segments in a circle