What is the explicit formula for this sequence?
5 , 10 , 15 , 20 , 25 , ...
an = 5n
an = 10 - 5n
an = 1 + 4n
an = 9 - 4n
gave you the options so you get what its asking cus i dont get it explain and il solve

Question

What is the explicit formula for this sequence?
5 , 10 , 15 , 20 , 25 , ...
an = 5n
 	an = 10 - 5n
 	an = 1 + 4n
 	an = 9 - 4n
gave you the options so you get what its asking cus i dont get it  explain and il solve

parthkohli · Answer

You check the formulae by replacing n with 1 and checking if you get 5.
Then replace n with 2 and see if you get 10.

parthkohli · Answer

And so on....

anonymous · Answer

If you're wondering what the formula was to get the options, it was:
$$a_{n} = a_{1} + (n - 1)d$$

parthkohli · Answer

@Calcmathlete this can be made easier here :D

anonymous · Answer

lol. I suppose :)

anonymous · Answer

okay

anonymous · Answer

THe question said: "What is the explicit formula for this sequence?", so I thought that's what the question was.

parthkohli · Answer

Yep :) but you can derive easier formulae. Like this - 4,8,12,16.... has a formula an = 4n so that's easier.

parthkohli · Answer

We could also have had something like an = 4 + (n - 1)4 but that's like very unsimplified.