Question

For option b why does doing 34=3n-1 give u the answer instead of 3(34)-1=tn on question 8

Answer 1

Answer:

Correct option are:

A and C

Step-by-step explanation:

Question 8

To know which of the options contain 34, we test each of them

`t_n=6+(n-1)4`

For n = 8

`\begin{gathered} t_8=6+(8-1)(4) \\ =6+28 \\ =34 \end{gathered}`

Also

`\begin{gathered} t_1=12,d=5.5,t_n=34 \\ \\ t_n=12+(n-1)5.5 \\ \\ 34=12+(n-1)5.5 \\ 34-12=(n-1)5.5 \\ n-1=(22)/(5.5) \\ \\ n=4+1=5 \end{gathered}`

A and C are the correct options