a. [ 8⁶.4320⁰ ] : 8⁵

= [ 8⁶.1] :8⁵

= 8⁶ : 8⁵

=8

b) (22+18)⁴ : 40³ + 2².3

= 40⁴ : 40³ + 2².3

= 40 + 2².3

= 40 + 4.3

=40 + 12

=52

1.x-3/4=9/4

1.x      = 9/4 + 3/4

1.x      = 3

  x      = 3 : 1 

  x      = 3  

3/4 x 8/9 x 15/16 x 24/25 x 35/36

=(3/4 x 8/9) x 15/16 x (24/25 x 35/36)

=2/3 x 15/16 x 14/15

=2/3 x (15/16 x 14/15)

=2/3 x 7/8

=7/12

A1={H;Ô;C;I;M;N}

A={1;2;3;4}

a) 58.59+59.43-59

= (58+43-1).59

= 100.59

=5900

b) 3³.22-3³.19

= 27.22-27.19

=( 22-19).27

=3.27

=81

c)(9⁶.57+43.9⁶):9⁶

= 9⁶.(57+43):9⁶

=9⁶.100:9⁶

=(9⁶:9⁶).100

=1.100

=100

d.118.45+55.118-18.100

=(45+55).118-18.100

=100.118-18.100

=100.(118-18)

=100.100

=10000

11+14+17+...+206+209

số số hạng: (209-11):3+1= 67

tổng: (209+11).67:2=7370

5.25.6+3.37.10+2.38.15

= 5.6.25+3.10.37+2.15.38

= 30.25+30.37+30.38

= 30.(25+38+37)

= 30. 100

= 3000