Answer:

Explanation:
The
th term of an arithmetic sequence is explicitly defined as
where
is the first term of the sequence and
is the the common difference.
From the given first five terms of the sequence we can see that the first term is
so
.
The common difference,
, can be calculated by
so we'll find the common difference of the given sequence by letting 
.
Now let's plug everything we know.



If that is -2+1+4+13 I think it should be 16
Answer:
Step-by-step explanation:
a1=2/3
sequence is 2/3,3/4,4/5,...
for numerator a1=2
d=3-2=1
numerator of nth term=a1+(n-1)d=2+(n-1)×1=2+n-1=n+1
denominator = 1 more than numerator=n+1+1=n+2
so an=(n+1)/(n+2)
or for denominator a1=3,d=4-3=1
denominator of nth term=3+(n-1)×1=3+n-1=n+2
an=(n+1)/(n+2)
Answer:
The lady is on the second door
Step-by-step explanation:
we have that
The sign on the first door reads "In this room there is a lady, and in the other one there is a tiger"
The sign on the second door reads "In one of these rooms, there is a lady, and in one of them there is a tiger."
so
The sign on the second door is true
The sign on the first door is true or false
Since one of these signs is true and the other is false, the sign in the first door must be false
therefore
The lady is on the second door