Question

If x,y,z are in A.P., then $3^{-x}$, $3^{-y}$, $3^{-z}$are in :

• A. A.P.
• B. G.P.
• C. H.P.
• D. None

Answer 1

The correct option is B

G.P.

$3^{-x}$ × $3^{-z}$ = $3^{-(x+z)}$ = $3^{-\left(2y\right)}$ = $(3^{-y}{)}^2$

⇒ $3^{-x}$, $3^{-y}$, $3^{-z}$ are in G.P.