Tính nhanh: 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64
Bài 15; Tính nhanh
a,1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64
=........................................................................
=........................................................................
=........................................................................
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b,1/2x3 + 1/3x4 + 1/4x5 + 1/5x6
=.......................................................................
=.......................................................................
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a,1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64
=........................................................................
=........................................................................
=........................................................................
=........................................................................
b,1/2x3 + 1/3x4 + 1/4x5 + 1/5x6
=.......................................................................
=.......................................................................
=........................................................................