This is Q of sequence series hlp me1 2 4 8 16 ..find nth term of the series find sum of first n term?

Answer 1

If you remember taking sequences, you'll recall that there are three main types:

1)Arithmetic Sequence

2)Geometric Sequence

3)Varied-formula Sequence

If the difference between the terms is additional or subractional then its an arithmetic sequence, lets check if this is the case, subtract the first term from the second and the second from the third etc : 1, 2, 4, 8, 16

2-1=1

4-2=2

8-4=4....all the answers are not constant so it is not an arithmetic sequence

In a geometric sequence, the difference is in multiplication or division so we divide like this t2/t1 then t3/t2 and then t4/t3 and so on:

2/1=2

4/2=2

8/4=2...all the numbers are constant so this sequence we have here is a geometric sequence to find the nth term we use a formula it varies from the kind of sequence you are using, the formula for a geometric sequence is: tn=t1*r^(n-1)

The formula might look confusing so ill write it down for you: "term n= term 1 multiplied by common ratio to the power n-1"

The 'common ratio' is the constant so in this case it equals 2.

tn=1*2^(n-l) that is the farthest you can go, if the question gives you the nth term then you may substitute it yourself. You didn't make yourself very clear with the last part of your question...