Question

42×39+43×61怎么提取公因数？

Answer 1

你看42,43就差那麼一点，
所以=42*39+43*61
=42*39+42*61+61
=42*(39+61)+61
=42*100+61
=4261

Answer 2

将43换成（42+1）
42*39+43*61
=42*39+（42+1）*61
=42*39+42*61+61
=42*（39+61）+61
=42*100+61
=4200+61
=4261

Answer 3

42×39+43×61＝4261
这些数是互质数，没有公因数。

Answer 4

解,原式=(43-1)x39+43x61 互 =43x(39+61)-39 =43x100-39 =4300-39 二4261

Answer 5

42x39+43x61
=(43-1)x39+43x61
=43x39+43x61-1x39
=43x(39+61)-39
=43x100-39
=4300-39
=4261