Определите при каких значениях переменной дробь 1/x^2−8x−20 не имеет смысла. В ответе укажите наибольшее из этих значений.

Нарисуйте два сонаправленных вектора, которые соответвствуют силам 3 Н и 5 Н. Определите их результирующую R для двух случаев:

а) векторы направлены динаково

б) векторы направлены противоположно

СОКРАТИТЕ 2 ТЕЕЕКСТА СРООЧНО!!!ОНИ МАЛЕНЬКИЕ!МОЖЕТ ЧТО-ТО ПЕРЕДЕЛАЕТЕ,ПЛИИЗ ОЧЕНЬ НУЖНО СРОЧНОО

Know to native Americans as the `Mountain lying down`, the Grand Canyon stretches for 443 kilometres where the Colorado River cuts through northwest Arizona. The canyon is a baby by geological standards - only five or six million years old, although the rock at the bottom are almost two billion years old. It is the incredible colors of the different layers of rock that delight visitors - over five million of them every year. Surprisingly though, after ma the long journey there, the average visitor spends only fifteen minutes looking at the Canyon. Even so, victors should still be careful: every year an average of five people fall over the edge.

A viewer`s opinion: `It`s just incredible, you feel as you have died and gone to heaven.`

The location for a number of Hollywood films, including Indiana Jones and the Last Crusade, the city of Petra was boilt in rocky cliffs more than 2,000 years ago, and was once an important commercial city. Temples, palaces, and a huge amphitheatre were all cut of the cliffs, whose amazing colours give the city its rose-red appearance. Historians believe that the citizens of Petra had to abandon it around 551 AD and this incredible archaeological site was forgotten by the West, until a Swiss traveller `rediscovered` it in 1812.

A viewer`s option: `It`s very difficult to imagine how enormous and how splendid it is from photographs - you just have to see it in person. It`ll blow your mind!`