用简便方法计算:40 2/3 * 39 1/3 99²+198+1

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用简便方法计算:40 2/3 * 39 1/3 99²+198+1
用简便方法计算:40 2/3 * 39 1/3 99²+198+1

用简便方法计算:40 2/3 * 39 1/3 99²+198+1
40又2/3×39又1/3
=(40+2/3)×(40-2/3)
=40²-(2/3)²
=1600-4/9
=1599又5/9
99²+198+1
=99²+2×99×1+1²
=(99+1)²
=100²
=10000