CBSE Class 10-Mathematics: Chapter – 5 Arithmetic Progressions Part 8 (For CBSE, ICSE, IAS, NET, NRA 2022)
Get top class preparation for CBSE/Class-10 right from your home: get questions, notes, tests, video lectures and more- for all subjects of CBSE/Class-10.
Question 3:
Which term of the AP: … is ?
Answer:
First term , Common difference and
Using formula d, to find term of arithmetic progression,
,
It means term of the given AP is equal to .
Question 4:
Find the number of terms in each of the following APs:
(i)
(ii)
Answer:
(i)
First term , Common difference
And
Using formula , to find nth term of arithmetic progression,
Therefore, there are terms in the given arithmetic progression.
(ii)
First term , Common difference
And
Using formula , to find nth term of arithmetic progression,
Therefore, there are terms in the given arithmetic progression
Question 5:
Check whether is a term of the AP:
Answer:
Let is the nth of AP which means that
Here, First term , Common difference
Using formula , to find term of arithmetic progression,
But, n cannot be in fraction.
Therefore, our supposition is wrong. cannot be term in AP.
Question 6:
An AP consists of terms of which term is and the last term is . Find the term.
Answer:
An AP consists of 50 terms and the term is equal to and
Using formula , to find term of arithmetic progression,
And
These are equations consisting of two variables.
Using equation , we get
Putting value of a in the equation ,
Putting value of d in the equation, ,
Therefore, First term and Common difference
To find term, we use formula
which is used to find nth term of arithmetic progression,
Therefore, term of AP is equal to