Question

if x1,x2,x3,x4,x5 are in Arithmetic progression​

Answer 1

what I've to do in this question pls mention it properly.

if. the question is to show. then I can try

a1 = x1

d = x2 - x1 = x1

now u have both first term and the common difference...

so just compare it with others term with the formula

an th term = a1 + ( n-1 ) x d

now suppose u have to compare 【 x4 is in A.P. or not 】 , so how u have to do is... very simple just put down the given value in the formula.

a4 th term = a1 + (n-1 ) x d

x4 = x1 + ( 4-1 ) x x1

x4 = x1 + x3

x4 = x4

hence L.H.S = R.H.S

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