1001的平方-202202+101的平方
=1001²-2×1001×101+101²
=(1001-101)²
=900²
=810000
99的平方+198+1
=99²+2×99×1+1²
=(99+1)²
=100²
=10000
7又4分之3×8又4分之1
=(8-1/4)(8+1/4)
=64-1/16
=63又15/16
1.02×0.98
=(1+0.02)(1-0.02)
=1²-0.02²
=1-0.0004
=0.9996
1001的平方-202202+101的平方
=1001²-2×1001×101+101²
=(1001-101)²
=900²
=810000
99的平方+198+1
=99²+2×99×1+1²
=(99+1)²
=100²
=10000
7又4分之3×8又4分之1
=(8-1/4)(8+1/4)
=64-1/16
=63又15/16
1.02×0.98
=(1+0.02)(1-0.02)
=1²-0.02²
=1-0.0004
=0.9996