已知整数X,Y满足1/X-1/Y=1/182,且X/7=Y/13,求XY的值
1/X-1/Y=1/182,182y-182x=xy
X/7=Y/13,即x=7t,y=13t,t≠0,代入得
182(13t)-182(7t)=(7t)(13t)
2366t-1274t=91t²
1092t=91t²
t=12
X=84
Y=156
x/7=y/13
x=7y/13代入1/x-1/y=1/182
1/(7y/13)-1/y=1/182
13/7y-1/y=1/182
6/7y=1/182
7y=6*182
y=156
x=7*156/13=84
x/7=y/13→y=13x/7
1/x-1/y=1/182→1/x-7/13x=1/182
即:20/13x=1/182→x=280
代入:y=13·280/7=520
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