Предмет: Алгебра, автор: l89123951754

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* - умножение
( frac{x}{ x^{2}-4 } + frac{x}{(x-2) ^{2} } ) * frac{(2-x)}{2x} - frac{x}{x+2}

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Автор ответа: viktorlicey1
0
х(х-1)/(4-х^2)
решение во вложении
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3.3. Прочитайте и переведите текст.
Stem Structure and Function
The stem of a plant has several important functions. It carries water and minerals to the leaves and the flowers. The stem also transports food between the leaves and the roots.
In addition, the stem supports the aboveground parts of a plant. Examination of a bare woody stem will give you a great deal of information about stems. Look at the woody stem. At the tip of this stem and along the side you will notice several structures called buds. The second picture (figure 1.6) shows a longitudinal section of a bud. The outer layers of a bud are called bud scales, which are modified leaves that form a protective covering. If you were to peel away the bud scales, you would find a soft mass of green tissue. This tissue is called the shoot apex. In this part of the bud, cell division occurs and new tissues are produced. Notice that new leaves of the plant can form at the shoot apex.
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Ответьте на вопросы по тексту (упр. 3.3):
1.What are the most important functions of a stem?
2.What can one see at the tip and along the sides of a stem?
3.What are bud scales?
4.In which part of the bud are new tissues produced?
5.What kinds of buds do you know?
6.What is the difference and lateral buds?
7.Can you find out how much the stem grew in length during the growing season? How?
8.What is the difference between a leaf scar and a bundle scar?
9.What kind of function do lenticels fulfill?
3.12. Укажите, являются ли данные утверждения истинными или ложными в соответствии с содержанием текста (упр. 3.3):
1.The stem absorbs water and minerals from soil.
2.One of the main functions of a stem is to transport food between the leaves and the roots.
3.Bud scales are the inner layers of a bud.
4.Having peeled away the bud scales, one can find a soft mass of green tissue, called the shoot apex.
5.Leaves and flowers can arise from both terminal and lateral buds.
6.Buds continue growing between growing seasons.
7.An internode is a section of a stem between nodes.
8.At leaf scars one can see bundle scars.
9.The bark of a woody stem has small round openings, called budscale scars.
10.Lenticels provide the exchange of gases between the atmosphere and the tissues of the stem.
Расположите пункты плана в логической последовательности на основании содержания текста (упр. 3.3):
1.The structure of a bud
2.Lenticels no
3.Major functions of a stem
4.Buds during and between growing seasons
5.Terminal and lateral buds
6.A node
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