Question

Determine an ap whose n term is 1) an=n^2+5n

Answer 1

Answer:

There is no such Ap

Step-by-step explanation:

put the value of n as 1,2,3...

A1 = 1+5=6

A2=4+10=14

A3=9+15=24

for this to be an Ap a3-a2=a2-a1 as common diff is same for the ap

24-14=14-6

10=8

but 10 is not equal to 8 thus this is not an ap

Answer 2

Given:-

aₙ=n²+5n

To Find:-

A.P. of the aₙ.

Solution:-

a₁=(1)²+5(1)=1+5=6

a₂=(2)²+5(2)=4+10=14

a₃=(3)²+5(3)=9+15=24

a₄=(4)²+5(4)=16+20=36

∵ d(common difference) is continuously changing...

∴ It is not forming an AP.