Предмет: Алгебра, автор: overdossse

1) Назовите уравнение, корнем которого является число
1 или —1:
а) х2 + 19x — 20 = 0;
б) 2x2 + 18х + 16 = 0; ​

Ответы

Автор ответа: megaamir555
1

Ответ:

a) 1

б) -1

Объяснение:

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 Mineralogy is the identification of minerals and the suady study  properties, origin, and classification.  The properties of minerals are studied  under the convenient subdivisions of chemical mineralogy, physical  mineralogy, and crystallography. The properties and classification of individ minerals, their localities and modes of occurrence, and their uses are studied under descriptive mineralogy. Identification according to chemical,  physical,  and crystallographic properties is called determinative mineralogy.
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 The various classes of chemical compounds that include a majority of minerals are as follows: (1) elements, such as gold, graphite, diamond, and sulfur, that occur in the native state, that is, in an uncombined form: (2) students,  which are minerals composed of various metals combined with sulfur. Many important  ore minerals, such as galena and sphalerile, are in this class: (3)  sulfo salts, minerals composed of lead, copper, or silver in combination With sulfur and one or more of the following: antimony, arsenic, and bismuth (4) orides, minerals composed of a metal in combination with oxygen, such as hematite. Mineral oxides that contain water, such as diaspore, or the bydroxyl such as bog iron ore, Feo(oH), also belong to this group; (5) (OF) group, halides, composed of metals in combination with chlorine, fluorine, bromine, or iodine; halite, Naci, is the most common mineral of this class; (6) carbonates, minerals such as calcite, containing a carbonate group G) phosphates, minerals such as apatite, Ca5(F,Cl)(PO4)3, that contain a phosphate group; (8) sulfates, minerals such as barite, Baso4, containing a sulfate group; and (9) silicates, the largest class of minerals, containing various elements in combination with silicon and oxygen, often with complex chemical structure, and minerals composed solely of silicon and oxygen (silica). The silicates include the minerals comprising the feldspar, mica, pyroxene, quartz, and zeolite and amphibole families.
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