what is the nth term expression for 4 7 10 13
Answers
Answer:
The nth term is 28
Step-by-step explanation:
hope it will help you
Answer:
3n-2
Step-by-step explanation:
We should recognise that
1
,
4
,
7
,
10
,
13
...
.
is an A.P. with a common difference of 3.
d
=
3
The expression for the nth term can be determined from the formula, but there is a short cut.
T
n
=
d
×
n
+
?
?
?
As soon as see that
d
=
3
, you will know that the expression for the nth term with start with
T
n
=
3
n
Now you just have find what must be added or subtracted to start at the correct first term.
Let
n
=
1
→
3
×
1
=
3
,
but
T
1
must be
1
,
so subtract 2
Let
n
=
2
→
3
×
2
=
6
but
T
2
must be
4
.
so subtract 2
It would seem that the expression we want is:
T
n
=
3
n
−
2
Check with
T
3
which must be 7.
3
×
3
−
2
=
7
T
n
=
3
n
−
2