Westonci.ca connects you with experts who provide insightful answers to your questions. Join us today and start learning! Discover detailed answers to your questions from a wide network of experts on our comprehensive Q&A platform. Get quick and reliable solutions to your questions from a community of experienced experts on our platform.
Sagot :
The arithmetic sequence has a 2nd term of -2 and a 7th term of 18 has the following answers.
What is arithmetic progression?
An progression or arithmetic sequence may be a sequence of numbers specified the difference between the consecutive terms is constant.
Main body:
General formula for arithmetic sequence
a + (n-1)d = aₙ
arithmetic sequence has a 2nd term of -2 , which means
a+d = -2
a = -(d+2) ---------(1)
7th term of 18 , which means
a+ 6d = 18
substituting value from equation 1,
-(d+2) +6d = 18
-d -2 +6d = 18
5d = 20
d = 5
using d= 5 in equation 1,
a = -(5+2)
a =-7
A) 10th term
=a +9d
= -7+9*5
= 38
B) recursive formula for the sequence = aₙ+1=aₙ+d .
Hence for the given sequence , it is
a₃ = a₂ +d
a₃ = -2+5
a₃ = 3
C) sum of first 10 terms
Sₙ = n/2{2a+ (n-1)d}
S₁₀ = 5 {2*-7 + 9*5}
S₁₀ = 5[ -14 +45]
S₁₀ = 5*31
= 105
Hence the sum of the first 10 terms is 105.\
To know more about arithmetic progression , visit:
https://brainly.com/question/6561461
#SPJ1
Thank you for visiting. Our goal is to provide the most accurate answers for all your informational needs. Come back soon. Thanks for stopping by. We strive to provide the best answers for all your questions. See you again soon. Get the answers you need at Westonci.ca. Stay informed with our latest expert advice.