ImJustSimple2 ImJustSimple2
  • 10-10-2020
  • Mathematics
contestada

The sum of the first three terms of a sequence is 6 and the fourth term is 16

Respuesta :

unicorn3125
unicorn3125 unicorn3125
  • 12-10-2020

Answer:

              a₁ = -5, d = 7,  a₂ = 2, a₃ = 9, a₄ = 16

equation of sequence:    [tex]\boxed{\bold{a_n=7n-12}}[/tex]

Step-by-step explanation:

a₁ + a₂ + a₃ = 6    

a₁ + a₁ + d + a₁ + 2d = 6

3a₁ + 3d = 6

a₁ + d= 2     ⇒ a₁ = 2 - d

a₄ = 16

a₁ + 3d = 16

2 - r + 3d = 16

2d = 14

d = 7

a₁ = 2-7 = -5

a₁ = -5, d = 7   ⇒  a₂ = -5+7 = 2, a₃ = 2+7 = 9, a₄ = 9+7 = 16

equation of arithmetic sequence:

[tex]a_n=a_1+d(n-1)\\\\a_n=-5+7(n-1)\\\\\underline{a_n=7n-12}[/tex]

Answer Link

Otras preguntas

What is a Punnett Square? How can it be used to analyze possible genetic outcomes for offspring
a change in an organism's surroundings that causes it to react is called
What book is Lady Justice standing on?
give an example of a problem that uses the expression 9.5 x (8+12.5)
In HIJ∆ determine the measure of H∠ to the nearest degree.
Which of the following is a component of healthy soil ecosystems? a. fungi b. bacteria c. nematodes d. all of the above
Barnabus caught 84 fish in 4 days. Each day he caught 10 more than on the day before. How many fish did he catch each of the 4 days
If a person walks 1.3 m/s, how far will that person walk in 300 s?
Which answer shows this equation written in standard form? 8 – 1(x – y) = –3x + 5 A. 2x + y = –3 B. 2x – y = –3 C. –4x + y = –3 D. 2x + y = 13
33 is 50% of what number