Question

The formula for the nth term of an arithmetic sequence can be found using the formula a(n)=a (1)+(n-1)d. Which of the following is equivalent to this equation?

a. n=a(n)
b. n=a(n)+a(1)-d/d
c. n=a(n)-a(1)
d. n=a(n)-a(1)+d/d

Answer 1

D.

Explanation:

:)

Answer 2

The formula is given as


`a_(n) = a_(1)+(n-1)d` , multiplying out the bracket gives

`a_(n)= a_(1)+nd-d`, rearranging to make
`n` the subject

`a_(n)- a_(1)+d=nd`

`( a_(n)- a_(1)+d )/(d)=n`

Hence, the correct answer is option d