Progression (Sequence and Series)Hard
Question
Suppose a,b,c are in AP and a2, b2, c2 are in GP. If a < b < c and a + b + c = 
, then the value of a is
, then the value of a is Options
A.
B.
C.
D.
Solution
Since, a,b,c are in AP
Let a = A - D,b = A, c = A + D
Given, a + b + c =
⇒ (A - D) + A + (A + D) =
⇒ 3A =
⇒ A =
∴ The number are
Also,
are in GP
⇒
⇒
⇒
⇒
∴
So, out of the given values,
is the right choice.
Let a = A - D,b = A, c = A + D
Given, a + b + c =
⇒ (A - D) + A + (A + D) =
⇒ 3A =
⇒ A =
∴ The number are
Also,
are in GP ⇒
⇒
⇒
⇒
∴
So, out of the given values,
is the right choice.Create a free account to view solution
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