求方程x^2y-3x^2=4的整数解.

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求方程x^2y-3x^2=4的整数解.求方程x^2y-3x^2=4的整数解.求方程x^2y-3x^2=4的整数解.x^2y-3x^2=4x^2(y-3)=4所以x^2=4/(y-3)因为x,y是整数所

求方程x^2y-3x^2=4的整数解.
求方程x^2y-3x^2=4的整数解.

求方程x^2y-3x^2=4的整数解.
x^2y-3x^2=4
x^2(y-3)=4
所以x^2=4/(y-3)
因为x,y是整数
所以y-3只可能是4的正约数1,2,4
所以y可能是4,5,7
当y=4时,x^2=4/(4-3)=4,x=±2
当y=5时,x^2=4/(5-3)=2,x=±√2,不合题意,舍去
当y=7时,x^2=4/(7-3)=1,x=±1
所以方程x^2y-3x^2=4的整数解为:
x1=2,y1=4
x2=-2,y2=4
x3=1,y3=7
x4=-1,y4=7

x^2(y-3)=4,而x,y是整数,故x^2=1,y-3=4或x^=4,y-3=1。故x=1,y=7或x=-1,y=7或x=2,y=4或x=-2,y=4

x=+2或-2 y=4