2003² - 2002.2003

= 2003.(2003 - 2002)

= 2003 . 1

= 2003

-------------------

7(x - 2) + 2³ = 2.5²

7(x - 2) + 8 = 2.25

7(x - 2) = 50 - 8

7(x - 2) = 42

x - 2 = 42 : 7

x - 2 = 6

x = 6 + 2

x = 8

-------------------

23 + (27 - 7.6) - (94.7 - 27.99)

= 23 + 27 - 42 - 658 + 2673

= 23 + (27 + 2673) - (42 + 658)

= 23 + 2700 - 700

= 23 + 2000

= 2023

`2023^2-2022.2023`

`=2023.2023-2022.2023`

`=2023.(2023-2022)`

`=2023.1`

`=2023`

__

` 23 + (27 - 7.6) - (94.7 - 27.99)`

` = 23 + (27 - 42) - (658 - 2673)`

` = 23 + (-15) - (-2015)`

` = 8 + 2015`

` = 2023`

\(2023^2-2022.2023\)

\(=2023\left(2023-2022\right)\)

\(=2023.1\)

\(=2023\)

\(23+\left(27-7.6\right)-\left(94.7-27.99\right)\)

\(=23+27-7.6-94.7+27.99\)

\(=23+\left(27+27.99\right)-\left(7.6+94.7\right)\)

\(=23+27\left(1+99\right)-7.\left(6+94\right)\)

\(=23+27.100-7.100\)

\(=23+2000\)

\(=2023\)

16+(27-7.6)-94.7-27.99

=16+27-7.6-94.7-27.99

16+27(1+99)-7(6+94)=+2700-700=2016

đúng thì tk cho mk nha

2016 nha ban

Đáp án là 2016 bạn nha

\(A=\frac{2}{1.4}+\frac{2}{4.7}+\frac{2}{7.10}+...+\frac{2}{97.100}\)

\(A=2\left(\frac{1}{1.4}+\frac{1}{4.7}+\frac{1}{7.10}+...+\frac{1}{97.100}\right)\)

\(A=2\left(1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+...+\frac{1}{97}-\frac{1}{100}\right)\)

\(A=2\left(1-\frac{1}{100}\right)\)

\(A=2.\frac{99}{100}=..............\)

Tự làm nốt nha

what?

=2016 nha

1.

`16 + (27 - 7.6 ) - (94 -7 - 27.99)`

`= 16+ 27 - 7.6 - 94 + 7 + 27.99`

`= 16 + 27(99 +1) - 7(6-1) - 94`

`= -78 + 27.100 - 7.5`

`= 2587`

2.

`A = 2/1.4 + 2/4.7 + 2/7.10 +...+ 2/97.100`

`A= 2(1/1.4 + 1/4.7 + 1/7.10 +...+1/97.100)`

`3A = 2 (3/1.4 + 3/4.7 + 3/7.10+...+ 3/97.100)`

`3/2 A = 1 - 1/4 + 1/4 - 1/7 +...+ 1/97 - 1/100`

`3/2A = 1 - 1/100`

`3/2 A= 99/100`

`A= 99/100 : 3/2`

`A=33/50`

Vậy `A= 33/50`

1.16+(27-7.6)-(94-7-27.99)=16+27-7.6-94+7+27.99

                                           =(27+27.99)+(27+7-94)+16

                                           =27.100-60+16

                                           =2700-44=2656

2.A=\(\dfrac{2}{1.4}+\dfrac{2}{4.7}+\dfrac{2}{7.10}+...+\dfrac{2}{97.100}\)

     =\(\dfrac{1}{1}-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+...+\dfrac{1}{97}-\dfrac{1}{100}\)

     =\(1-\dfrac{1}{100}=\dfrac{99}{100}\)

1) \(16+\left(27-7.6\right)-\left(94-7-27.99\right)\)

=\(16+27-7.6-94+7+27.99\)

=\(\left(27+27.99\right)+\left(-7.6+7\right)+\left(16-94\right)\)

=\(27\left(1+99\right)+7\left(-6+1\right)-78\)

=\(27.100-7.5-78=2700-35-78=2587\).

2) \(A=\dfrac{2}{1.4}+\dfrac{2}{4.7}+\dfrac{2}{7.10}+...+\dfrac{2}{97.100}\)

\(A=\dfrac{2.3}{1.4.3}+\dfrac{2.3}{4.7.3}+\dfrac{2.3}{7.10.3}+...+\dfrac{2.3}{97.100.3}\)

\(A=\dfrac{2}{3}.\left(\dfrac{3}{1.4}+\dfrac{3}{4.7}+\dfrac{3}{7.10}+...+\dfrac{3}{97.100}\right)\)

\(A=\dfrac{2}{3}.\left(\dfrac{1}{1}-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{10}+...+\dfrac{1}{97}-\dfrac{1}{100}\right)\)

\(A=\dfrac{2}{3}.\left(\dfrac{1}{1}-\dfrac{1}{100}\right)=\dfrac{2}{3}.\dfrac{99}{100}=\dfrac{33}{50}\)

101.27+27.99+6363+63.99

=101.27+27.99+63.101+63.99

=101.(27+63)+99.(27+63)

=101.90+99.90

=(101+99).90

=200.90

=18000

 3 + 6 + 9 + ..... + 24 + 27

= ( 3 + 27 ) + ( 6 + 24 ) + ( 9 + 21 ) + ( 12 + 18 ) + 15

=     30       +        30     +       30     +        30      + 15

= 120 + 15

= 135

  13,5 x 1420 + 4,5 x780 x3

= 19170 + 10530

= 29700

Bài 1 :

\(3+6+9+....+24+27.\)

Dãy số trên có :

\(\left(27-3\right)\div3+1=9\) ( số )

Tổng của dãy số trên là :

\(\left(27+3\right)\times9\div2=135\)

Bài 2 :

\(13,5\times1420+4,5\times780\times3\)

\(=13,5\times1420+\left(4,5\times3\right)\times780\)

\(=13,5\times1420+13,5\times780\)

\(=13,5\left(1420+780\right)\)

\(=13,5\times2200\)

\(=29700\)

a. 3(1+2+3...+9) = 3.45 = 3x40 + 3x5 = 135

b. 13.5x1420 + 13.5x780=13.5x2200=135x220=135x200+135x20=27000+2700=29700