数学问题已知正整数x,y满足x^2-y^2=24,求xy(x+y)的值
问题描述:
数学问题已知正整数x,y满足x^2-y^2=24,求xy(x+y)的值
答
x^2-y^2=24(x+y)(x-y)=2424=1×24=2×12=3×8=4×6x,y为正整数,x,y可能满足的方程如下:x+y=24x-y=1解得x,y不为整数,舍去.x+y=12x-y=2解得x=7 y=5x+y=8x-y=3解得x,y不为整数,舍去x+y=6x-y=4解得x=5 y=1x=7 y=5或x=5 ...