An important question from arithmetic progression chapter in which we have been asked to find its (i) first term, (ii) common difference (iii) 16 the term. If the nth term of a progression is (4n – 10) show also that it is an AP.
Book – RS Aggarwal, Class 10,
Arithmetic Progression, chapter 5A, question no 6
Given nth term of AP is 4n−10
Putting n=1,2,3,4,....., we get
At n=1:4n−10=4×1−10=4−10=−6
At n=2:4n−10=4×2−10=8−10=−2
At n=3:4n−10=4×3−10=12−10=2
At n=1:4n−10=4×4−10=16−10=6
We see that −6,−2,2,6,... are in AP as common difference is same.
Common difference =−2−(−6)=4.