Question

If
+6+4)*(+)(
are in A.P., prove that a, b, c are in A.P.
b​

Answer 1

Step-by-step explanation:

Answer

T

2

−T

1

=b

2

(c+a)−a

2

(b+c)

=c(b

2

−a

2

)+ab(b−a)=(b−a)(∑ab)

and T

3

−T

2

=c

2

(a+b)−b

2

(c+a)=(c−b)(∑ab)

∴b−a=c−b or 2b=a+c, which is true.