Question
Examine whether the following numbers are rational or irrational.
$\sqrt{7}\times\sqrt{343}$
$\sqrt{7}\times\sqrt{343}$
✓
Answer
As, $\sqrt{7}\times\sqrt{343}$
$=\sqrt{7\times343}$
$=\sqrt{2401}$
$=49,$ which is an integer
Hence, $\sqrt{7}\times\sqrt{343}$ is rational.
$=\sqrt{7\times343}$
$=\sqrt{2401}$
$=49,$ which is an integer
Hence, $\sqrt{7}\times\sqrt{343}$ is rational.
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