Advertisements
Advertisements
प्रश्न
If 7 times the seventh term of the AP is equal to 5 times the fifth term, then find the value of its 12th term.
उत्तर
7(a + 6d) = 5(a + 4d)
⇒ 2a + 22d = 0
⇒ a + 11d = 0
⇒ t12 = 0
APPEARS IN
संबंधित प्रश्न
In a school, students thought of planting trees in and around the school to reduce air pollution. It was decided that the number of trees, that each section of each class will plant will be the same as the class, in which they are studying, e.g., a section of class I will plant 1 tree, a section of class II will plant 2 trees, and so on till class XII. There are three sections of each class. How many trees will be planted by the students?
In an A.P., if the first term is 22, the common difference is −4 and the sum to n terms is 64, find n.
Find the sum of the first 22 terms of the A.P. : 8, 3, –2, ………
Find the sum of 28 terms of an A.P. whose nth term is 8n – 5.
Find the sum of first 12 natural numbers each of which is a multiple of 7.
The first term of an A.P. is 5, the last term is 45 and the sum of its terms is 1000. Find the number of terms and the common difference of the A.P.
Find the value of x for which (x + 2), 2x, ()2x + 3) are three consecutive terms of an AP.
The Sum of first five multiples of 3 is ______.
The given terms are 2k + 1, 3k + 3 and 5k − 1. find AP.
Complete the following activity to find the 19th term of an A.P. 7, 13, 19, 25, ........ :
Activity:
Given A.P. : 7, 13, 19, 25, ..........
Here first term a = 7; t19 = ?
tn + a + `(square)`d .........(formula)
∴ t19 = 7 + (19 – 1) `square`
∴ t19 = 7 + `square`
∴ t19 = `square`
