1-хкг
2-укг
3-zкг
{x+y+z=250 (1)
{x+y-z=-10 (2)
{y+z-x=110 (3)
(1)+(2) 2x+2y=240⇒x+y=120
(2)+(3) 2y=100⇒y=50кг
x+50=120
x=120-50
x=70кг
120+z=250
z=250-120
z=130кг
6x²-14x+4>0, метод интервалов:
1. 6x²-14x+4=0, x₁=1/3. x₂=2
2. + - +
------------(1/3)------------(2)------------------>x
3.
x∈(-∞;1/3)∪(2;∞)
D=b^2-4*a*c=4-16=-12
х1=4-(-12)/8= -16/8=-2
х2=4+(-12)/8=-8/8=-1
log(2) 3*log(3)16=4log(2) 3*log(3)2=4