Sin(180+60)+cos(360*3+120)-tg(2*360-150)=
=sin60+cos120-tg150=√3/2-1/2-tg(180-30)=
=√3/2-1/2-√3/3
1) х^2 - 5х - 24 = ( Х - 8 )( Х + 3 )
D = 25 + 96 = 121 = 11^2
Х1 = ( 5 + 11 ) : 2 = 8
Х2 = ( 5 - 11 ) : 2 = - 3
2) х^2 - 6х - 27 = ( Х - 9 )( x + 3 )
D = 36 + 108 = 144 = 12^2
X1 = ( 6 + 12 ) : 2 = 9
X2 = ( 6 - 12 ) : 2 = - 3
3) ( ( x - 8 )( x + 3 )) / ( ( x - 9 )( x + 3 )) = ( x - 8 ) / ( x - 9 )
А) y=-8; 0,4
б) x=-1; -0,7
Скачай фотомач и не парся)
2х+8х <15+13
10х <28
х <2,8