(bn) is an arithmetic sequence b is the first term, d is the difference find a) b7 b) b26 c) b231 d) bk e) bk+5 f) b2k in terms of b and d.

Question

please show me the correct formula and the answers

Answer 1

a_n = a₁ + (n - 1)d    This is the correct formula

 

b₇ = b + (7 - 1)d

b₇ = b + 6d

 

Can you follow this model?

Answer 2

The explicit formula for an arithmetic sequence is:

 

b_n = b + (n-1)d

• where bn is the nth term in the sequence
• b is the first term in the sequence
• n is the term number
• d is the common difference

 

a)  b₇ = b + (7-1)d = b + 6d

b)  b₂₆ = b + (26-1)d = b + 25d

c) b_k = b + (k-1)d

d)  b_k+5 = b + (k+5-1) = b + (k+4)d

e)  Can you do this one?