MCQ
If $3^{ x }=6561$, then $3^{x-3}=$
- A$81$
- ✓$243$
- C$729$
- D$27$
✓
Answer
Correct option: B.
$243$
$3^x=6561$
$\Rightarrow 3^x=3^8$
Comparing the exponent of both the sides, we get:
$x=8$
Now, $3^{x-3}=3^{8-3}$
$=3^5=243$
Hence, the correct alternative is option $(b).$
$\Rightarrow 3^x=3^8$
Comparing the exponent of both the sides, we get:
$x=8$
Now, $3^{x-3}=3^{8-3}$
$=3^5=243$
Hence, the correct alternative is option $(b).$
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