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ข้อความเดิมเขียนโดยคุณ banker

$y $=$ k\frac{x^2}{\sqrt{z}}$ ..........(1)
$y2 $=$ k\frac{4x^2}{\sqrt{2z}}$..........(2)


$\frac{(2)}{(1)}$ = $\frac{y2}{y}$ = $\frac{4\sqrt{z}}{\sqrt{2z}}$ .........(3)


$(3)^2$ = $(\frac{y2}{y})^2$ = $(\frac{4\sqrt{z}}{\sqrt{2z}})^2$ = $\frac{16z}{2z}$ = 8

$\frac{y2}{y}$ = $2\sqrt{2}$