Home
Class 10
MATHS
If the sum of the first n terms of an AP...

If the sum of the first n terms of an AP is `4n-n^(2)` , what is the first term (note that the first term is `S_(1)`)? What is the sum of first two terms? What is the second term? Similarly, find the 3rd, the 10th and the nth terms

Text Solution

Verified by Experts

The correct Answer is:
`S_(1) =3, S_(2) =4; a_(2)=1; a_(3)=-1, a_(10)= -15`
`a_(n) \ 5-2n`
Promotional Banner

Topper's Solved these Questions

  • PROGRESSIONS

    NCERT KANNAD|Exercise EXERCISE 6.4|3 Videos

  • PROGRESSIONS

    NCERT KANNAD|Exercise EXERCISE 6.5|7 Videos

  • PROGRESSIONS

    NCERT KANNAD|Exercise EXERCISE 6.2|16 Videos

  • POLYNOMIALS

    NCERT KANNAD|Exercise OPTIONAL EXERCISE [For extensive learning]|2 Videos

  • QUADRATIC EQUATIONS

    NCERT KANNAD|Exercise OPTIONAL EXERCISE|5 Videos

Similar Questions

Explore conceptually related problems

If the sum of the first n^(th) terms of an A.P is 4n-n^(2) , what is the first term (that is S_(1) ) ? What is the sum of first two terms? What is the second term? Similarly, find the 3^(rd) , the 10^(th) and the n^(th) terms.

IF the sum of the first n terms of an AP is 4n-n^2 , what is the first term (that is S_1 )? What is the sum of first two terms? What is the second term? Similarly, find the 3rd the 10th and the nth terms?

If the sum of the first n terms of an A.P. is 4n-n^(2) what is the first term? What is the sum of the first two terms? What is the second term? Find the 3rd, 10th, and the nth terms.

If the sum of the first 14 terms of an AP is 1050 and its first term is 10, find the 20th term.

IF the sum of three consecutive terms of an A.P. is 21, then first the first term.

The first n^(th) term of a AP is given by

If the sum of first p terms of an A.P is equal to the sum of the first q terms , then find the first (p+q) terms .

If the sum of first n terms of an A.P. is cn^(2) , then the sum of squares of these n terms is :

In an AP, the 5th term is 30 and 12th term is 65. What is the sum of first 20 terms?