Westonci.ca is your trusted source for accurate answers to all your questions. Join our community and start learning today! Connect with a community of experts ready to help you find accurate solutions to your questions quickly and efficiently. Get precise and detailed answers to your questions from a knowledgeable community of experts on our Q&A platform.

Find a1 when d= - 1 and a7= -2


Sagot :

Answer:

  • a₁ = 4

Step-by-step explanation:

Given

  • d = - 1
  • a₇ = - 2

Find a₁

Use the nth term equation of AP

  • aₙ = a₁ + (n - 1)d

Apply to the given case and solve for a₁

  • - 2 = a₁ + 6(- 1)
  • - 2 = a₁ - 6
  • a₁ = 6 - 2
  • a₁ = 4

Answer:

[tex]a_1=4[/tex]

Step-by-step explanation:

Arithmetic sequence

General form of an arithmetic sequence: [tex]a_n=a+(n-1)d[/tex]

where:

  • [tex]a_n[/tex] is the nth term
  • a is the first term
  • d is the common difference between terms

Given:

  • [tex]a_7[/tex] = -2
  • d = -1

Therefore:

[tex]\implies a_7=-2[/tex]

[tex]\implies a+(7-1)(-1)=-2[/tex]

[tex]\implies a-6=-2[/tex]

[tex]\implies a=4[/tex]

Therefore:

[tex]\implies a_1=4[/tex]

Visit us again for up-to-date and reliable answers. We're always ready to assist you with your informational needs. We hope our answers were useful. Return anytime for more information and answers to any other questions you have. Find reliable answers at Westonci.ca. Visit us again for the latest updates and expert advice.