1)Вычислите (предварительно сделав рисунок) площадь фигуры, ограниченной линиями: = ^2
y=4x-x^2
2)Найдите (предварительно сделав рисунок) объем тела, полученного при
вращении вокруг оси Ох фигуры, ограниченной линиями:
y=x^2-2
y=0
x=2
x=3
, очень надо(
Acid rains are very harmful to the atmosphere. Steel structures like bridges and towers corrode because of the acid. It also results in the peeling of paint from the painted surfaces like buildings. Stone structures get eroded because of the acid in the rain.
Acid rain shows adverse effects on human health, forests, sources of fresh water like rivers and streams, and on soil affecting different life forms surviving in these mediums.
What Is Smog?The term smog was first coined during the 1950s when it was used to describe a mixture of smoke and fog experienced in London. Major cities along the west coast of America were also experiencing a different type of air pollution.Smog occurs when emissions from industry, motor vehicles, incinerators, open burning and other sources accumulate under certain climatic conditions. There are two types of smog: summer (the type of smog first experienced in America) and winter (the one first noticed in London).Autumn And Winter Smog (Particles)During the cooler months (April to September), Melbourne is more affected by the accumulation of fine particles, which come from motor vehicle emissions, wood smoke, other combustion processes and photochemical processes in the air.Temperature inversions in winter mean that warm air higher in the atmosphere traps pollutants in the layer of cold air closer to the ground. These inversions can last for several days and cause 'scummy' brown hazed horizons until dispersed by wind or rain.The fine particles scatter sunlight, reduce visibility, soil buildings and fabrics and provoke existing respiratory diseases and other health problems.Photochemical Or Summer SmogIn the warmer months (October to March), photochemical smog (summer smog) is caused by the action of sunlight on a mixture of hydrocarbons and oxides of nitrogen. This smog contains secondary pollutants such as ozone, aldehydes and fine particles.
1) a) 2cosx-1=0
cosx=1/2
x=π/3+2πn, n∈Z
x=-π/3+2πn, n∈Z
б) cos²x+3sinx-3=0
1-sin²x+3sinx-3=0
-sin²x+3sinx-2=0
sinx=t
-t²+3t-2=0
D=9-8=1
t₁= (-3+1)/(-2)=1 t₂=(-3-1)/(-2)=2
sinx=1 sinx=2
x=π/2+2πn, n∈Z нет решения
в) 2sin²x-sin2x=cos2x
2sin²x-2sinxcos=cos²x-sin²x
3sin²x-2sinxcosx-cos²x=0 |÷sinx
3-2ctgx-ctg²x=0
ctgx=t
3t²-2t-1=0
D=4+12=16
t₁=(2+4)/-2=-3 t₂=(2-4)/-2=1
ctgx=-3 ctgx=1
x=arcctg(-3)+πn, n∈Z x=π/4+πn, n∈Z
x=π-arcctg3+πn, n∈Z
3) cos3x+cosx=0
2cos((3x+x)/2)cos((3x-x)/2 = 0
2cos2xcosx=0
cos2xcosx=0
cos2x=0 или cosx=0
2x=π/2+πn, n∈Z x=π/2+πn, n∈Z
x=π/4+πn/2, n∈Z