March 17, 2021

Chapters

## Exercise 1

The fourth term of an arithmetic sequence is and the sixth term is . Determine the sequence.

## Exercise 2

The first term of an arithmetic sequence is and the fifteenth term is . Find the common difference and the sum of the first fifteen terms.

## Exercise 3

Find the sum of the first fifteen multiples of .

## Exercise 4

Find the sum of the first fifteen numbers ending in5.

## Exercise 5

Find the sum of the first fifteen even numbers greater than .

## Exercise 6

Find the angles of a convex quadrilateral, knowing they are in arithmetic sequence and .

## Exercise 7

The lower leg of a right triangle is cm in length. Calculate the other two knowing that the sides of the triangle form an arithmetic sequence.

## Exercise 8

Calculate three numbers in an arithmetic sequence, whose sum is and the sum of their squares is .

## Solution of exercise 1

The fourth term of an arithmetic sequence is and the sixth term is . Determine the sequence.

Sequence =

## Solution of exercise 2

The first term of an arithmetic sequence is and the fifteenth term is . Find the common difference and the sum of the first fifteen terms.

## Solution of exercise 3

Find the sum of the first fifteen multiples of .

## Solution of exercise 4

Find the sum of the first fifteen numbers ending in .

## Solution of exercise 5

Find the sum of the first fifteen even numbers greater than .

## Solution of exercise 6

Find the angles of a convex quadrilateral, knowing they are in arithmetic sequence and .

The sum of the interior angles of a quadrilateral is .

Hence,

## Solution of exercise 7

The lower leg of a right triangle is in length. Calculate the other two knowing that the sides of the triangle form an arithmetic sequence.

is rejected because length is always positive.

## Solution of exercise 8

Calculate three numbers in an arithmetic sequence, whose sum is and the sum of their squares is .

Central term x