劳 ____ ____ ____ ____
每 ____ ____ ____ ____
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止 ____ ____ ____ ____
已知实数a满足a﹣1a=3,则a2+1a2的值为____
You can call us ________67654321 _______help.
三元一次方程组x-y=-1y-z=-1x+z=4的解是____