The 26th, 11th and the last term of an ap are 0,3 and respectively. find the common difference and the number of term plz don't give wrong answer
Answers
Answer:
Let a,d and n be the first term,common difference and number of terms of an AP respectively.
Now,
a
26
=a+25d=0 ...(1)
a
11
=a+10d=3 ...(2)
on doing (1)-(2) , we get
15d=−3
⇒d=
5
−1
On substituting the value of d in (1), we get
a+25×
5
−1
=0
⇒a=5
Again, a
n
=a+(n−1)d=
5
−1
On substituting the values of a and d, we get
5+(n−1)×
5
−1
=
5
−1
⇒(n−1)×
5
−1
=
5
−1
−5=
5
−26
⇒(n−1)=26
⇒n=27
Therefore,
d=
5
−1
,n=27
Answer:
ANSWER
Let a,d and n be the first term,common difference and number of terms of an AP respectively.
Now,
a
26
=a+25d=0 ...(1)
a
11
=a+10d=3 ...(2)
on doing (1)-(2) , we get
15d=−3
⇒d=
5
−1
On substituting the value of d in (1), we get
a+25×
5
−1
=0
⇒a=5
Again, a
n
=a+(n−1)d=
5
−1
On substituting the values of a and d, we get
5+(n−1)×
5
−1
=
5
−1
⇒(n−1)×
5
−1
=
5
−1
−5=
5
−26
⇒(n−1)=26
⇒n=27
Therefore,
d=
5
−1
,n=27