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What is the first term of an AP whose common difference is 2 and 31st term begin -88

User Arjan Knol
by
4.9k points

2 Answers

4 votes

a₁ = - 148

Step-by-step explanation:

The n th term of an AP is

= a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Given d = 2 and a₃₁ = - 88 , then

a₁ + (30 × 2) = - 88

a₁ + 60 = - 88 ( subtract 60 from both sides )

a₁ = - 148

User Sunil Kpmbl
by
5.1k points
4 votes

Answer:

a₁ = - 148

Explanation:

The n th term of an AP is


a_{n = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Given d = 2 and a₃₁ = - 88 , then

a₁ + (30 × 2) = - 88

a₁ + 60 = - 88 ( subtract 60 from both sides )

a₁ = - 148

User Warner Soditus
by
5.4k points