Question

Answer 1

\(y=\dfrac{2a+3}{a-5}=\dfrac{2\left(a-5\right)+13}{a-5}=2+\dfrac{13}{a-5}\)

Để y nguyên thì \(a-5\inƯ\left(13\right)=\left\{\pm1;\pm13\right\}\)

a-5	1	-1	13	-13
a	6	4	18	-8

 

Answer 2

\(x=\dfrac{a-4}{a}=1-\dfrac{4}{a}\)

Để x nguyên \(a\in\left\{\pm1;\pm2;\pm4\right\}\)