Tg ^2 X = A A^2 - 4A + 3 = ( A - 1 )*( A - 3) D = 16 - 4*1*3 = 16 - 12 = 4 V D = 2 A1 = ( 4 + 2 ) : 2 = 3 A2 = 2 : 2 = 1 ............................................. Tg^4X - 4Tg^2X + 3 = ( Tg^2X - 1)*( Tg^2X - 3 ) = ( TgX - 1)*( TgX + 1)*( TgX - V3)*(TgX + V3 )