Question

[Khánh Linh Phạm]

Tính giá trị biểu thức :

a, D= 1+2+4+8+16+...+1204

b, 18.123+9.4567.2+3.5310.6

c, E= 1+4+7+10+...+49+52+55+58-490

Answer 1

[linh phạm]

a,D=1+2+4+8+16+32+64+128+256+512+1024

   D=(1+2)+4+8+16+32+64+128+256+512+1024

   D=(4+4)+8+16+32+64+128+256+512+1024

   D=(8+8)+16+32+64+128+256+512+1024

   D=(16+16)+32+64+128+256+512+1024

   D=(32+32)+64+128+256+512+1024

   D=(64+64)+128+256+512+1024

   D=(128+128)+256+512+1024

   D=(256+256)+512+1024

   D=(512+512)+1024

   D=1024+1024

   D=2048

Answer 2

[linh phạm]

b, 18.123+9.4567.2+3.5310.6

  =18.123+(9.2).4567+(3.6).5310

  =18.123+18.4567+18.5310

  =18.(123+4567+5310)

  =18.10000

  =180000