Question

Сколькими способами можно расставить на полке томики стихов Пушкина Лермонтова Некрасова И Тютчева чтобы Пушкина стоял на первом месте Некрасов Тютчев стояли рядом

Answer 1

Возможно
1)Задача решается с помощью дерева(его нарисовать надо)
Пушкин
Тютчев Некрасов
Некрасов Тютчев

2 варианта

2)задача методом перечислений
первый у нас Пушкин, значит первый во всех вариантах

ПТН ПНТ
2 варианта

Answer 2

Calculation of the Number of Ways to Arrange the Books

To calculate the number of ways to arrange the books by Pushkin, Lermontov, Nekrasov, and Tyutchev on a shelf, with Pushkin in the first position and Nekrasov and Tyutchev next to each other, we can use the following approach:

1. Place Pushkin in the first position. 2. Treat Nekrasov and Tyutchev as a single entity, since they need to be placed next to each other. This reduces the problem to arranging three entities: Pushkin, the combined entity of Nekrasov and Tyutchev, and Lermontov. 3. There are 3! = 3 factorial ways to arrange these three entities. 4. Within the combined entity of Nekrasov and Tyutchev, there are 2! = 2 factorial ways to arrange them. 5. Therefore, the total number of ways to arrange the books is 3! * 2! = 6 * 2 = 12.

So, there are 12 different ways to arrange the books on the shelf, with Pushkin in the first position and Nekrasov and Tyutchev standing next to each other.

Please note that the sources provided do not directly answer this specific question. The calculation is based on the principles of combinatorics and factorial calculations.