[กิตติ]

ข้อ 5.$\dfrac{a-2554}{b-2544}=\left(\,\dfrac{a}{b} \right)^2 $

$\dfrac{a-2554}{b-2544}=\dfrac{\frac{a-2554}{ab} }{\frac{b-2554}{ab}} $

$\dfrac{a-2554}{b-2544}=\dfrac{\frac{1}{b} -\frac{2554}{ab}}{\frac{1}{a}-\frac{2554}{ab}} $

$\frac{1}{a} +\frac{1}{b}=\frac{1}{2554} $

$\frac{2554}{ab}=\frac{1}{a+b} $

$\dfrac{a-2554}{b-2544}=\dfrac{\frac{1}{b} -\frac{1}{a+b}}{\frac{1}{a}-\frac{1}{a+b}} =\dfrac{\frac{a}{b} }{\frac{b}{a} } $

$=\left(\,\dfrac{a}{b} \right)^2$