1)6+60=66 ; 2)0,6 - 5/3 = -16/15 ; 3) 0,2х20-1/3х9= 4-2=2 ; 4) 7х0,3+√8 + 1=3,1+√8; 5) 5х0,8-5+144=143 ;6) √49/9 - <span>√64/9 + 0,07х100= 7/3 - 8/3+7= 6 2/3; 7)1,8х16 - 2/3х12 = 28,8 -8 = 20,8; 8) 17:0,5 -1,5х30 = 34-45 = -11</span>
Сразу решение:
x-3x+1=6-x/2-x
-2x+1=6-x/2-x
-4x+2=12-3x
-4x+3x=12-2
-x=10
x=-10
Сos(t - 2π) = cos(2π - t) = cost
cos^2t = 1/(tg^2t + 1)
cos^2t = 1/(5/4 + 1)
cos^2t = 4/9
cost = -(2/3)
cost = (2/3)
ctg(-1) = - ctgt, tgt = -√5/2, tgt*ctgt = 1,ctgt = 1/tgt, ctgt = 1/(-√5/2)
sin(4π - t) = sint
sint = √(1 - cos^2x) = √[1 - (2/3)^2] = √5/3
<span>3х²-11х+7=0
D=121-12*7=37
x12=(11+-</span>√37)/6