I have 2 questions I am really struggling with related to finding the nth term....
Q1.
Sequence 1: 140,133,126...
Sequence 2: -59, -54, -49...
a) Find the nth term for each sequence and prove that the 17th term is the same on both sequences
b) there are 6 terms that are common to both sequences - can you find them all without writing out both sequences?
a)
S1: -7n+147
S2: 5n-64
therefore the 17th term is:
S1: -7(17)+147 = -119+147 = 28
S2: 5(17)-64 = 85-64 = 21
But the 17th term is not the same!
Also, i cannot find 6 terms that are common; for them to be common I've put -7n+147 = 5n-64 -> 211=12n - > n=211/12 - > but thats not an integer so not sure how to use this to find common terms - where am i going wrong?
Q1.
Sequence 1: 140,133,126...
Sequence 2: -59, -54, -49...
a) Find the nth term for each sequence and prove that the 17th term is the same on both sequences
b) there are 6 terms that are common to both sequences - can you find them all without writing out both sequences?
a)
S1: -7n+147
S2: 5n-64
therefore the 17th term is:
S1: -7(17)+147 = -119+147 = 28
S2: 5(17)-64 = 85-64 = 21
But the 17th term is not the same!
Also, i cannot find 6 terms that are common; for them to be common I've put -7n+147 = 5n-64 -> 211=12n - > n=211/12 - > but thats not an integer so not sure how to use this to find common terms - where am i going wrong?