168k views
3 votes
• (1) Which of the following are AP’s ? If they form an AP, find the common difference d and write 3 more terms.

• (a) 2,4,8,16……
• (b) -1.2, -3.2,-5.2,-7.2,…..
• ©2, 5/2 ,3, 7/2…..
• (d)-10,-6,-2.2, ……

1 Answer

4 votes

Answer:

Option (b) -1.2, -3.2,-5.2,-7.2,….. is AP

The common difference = -2

3 more terms are ⇒ -9.2 , -11.2 , -13.2

Option (c) 2, 5/2 ,3, 7/2….. is AP

the common difference = 1/2

3 more terms are ⇒ 4 , 9/2 , 5

Explanation:

AP ⇒ arithmetic progression is a sequence of numbers provide that the difference of any two successive members is a constant.

So, we will check the options:

• (a) 2,4,8,16……

The difference between 2 , 4 = 4 - 2 = 2

The difference between 4 , 8 = 8 - 4 = 4

So, option a is not AP

• (b) -1.2, -3.2,-5.2,-7.2,…..

The difference between -1.2 , -3.2 = -3.2 - (-1.2) = -3.2 + 1.2 = -2

The difference between -3.2 , -5.2 = -5.2 - (-3.2) = -5.2 + 3.2 = -2

So, option b is AP

The common difference = -2

3 more terms are ⇒ -9.2 , -11.2 , -13.2

• (c) 2, 5/2 ,3, 7/2…..

The difference between 2 , 5/2 = 5/2 - 2 = 1/2

The difference between 5/2 , 3 = 3 - 5/2 = 1/2

So, option c is AP

The common difference = 1/2

3 more terms are ⇒ 4 , 9/2 , 5

• (d) -10,-6,-2.2, ……

The difference between -10 , -6 = -6 - (-10) = -6+10 = 4

The difference between -6 , -2.2 = -2.2 - (-6) = -2.2 + 6 = 3.8

So, option d is not AP

So, the options that form an AP are b and c

User Danille
by
4.4k points