a) (-124) + 24 = -100
b) 37. 78 + 37. 22
=  37 . ( 78 + 22 )
=  37 . 100
= 3700

\(a) (-124) + 24 = -100 b) 37. 78 + 37. 22 = 37 . ( 78 + 22 ) = 37 . 100 = 3700\)

a) (- 124) + 24                                          b) 37 . 78 + 37 . 22

= - ( 124 - 24)                                              =37 . ( 78 + 22)

= - 100                                                        =37 . 100 

                                                                    3700

e: =5/7(5/11+2/11-14/11)

=5/7(-7/11)=-5/11

f: =-5/4(2/11+9/11)+1+3/4

=-5/4+7/4

=2/4=1/2

g: =-5/7(3/13+10/13)+1+5/7

=-5/7+1+5/7

=1

h: =7/4(29/5-9/5)+41/13

=-7+41/13=-50/13

\(=\left(\dfrac{1}{2}+\dfrac{1}{2}\right)-\left(\dfrac{5}{41}+\dfrac{36}{41}\right)=1-1=0\)

1/2-5/41+1/2-39/41

=(1/2+1/2)-(5/41+39/41)

=1-1

=2

   \(3^{^{ }2}\) . 5 + 2³.10  - 81: 3

= 9.5 + 8.10 - 27

= 45 + 80 - 27

= 125 - 27

= 98 

\(3^2\cdot5+2^3\cdot10-81:3\)

\(=9\cdot5+8\cdot10-3^4:3\)

\(=40+80-3^3\)

\(=120-27\)

\(=93\)

\(3^2.5+2^3.10-81:3\\=9.5+8.10-3^4 :3\\ =40+80-3^3\\ =120-27\\ =93\)

Đúng cho like nhé

\(=64\cdot\dfrac{-1}{8}+100\cdot\dfrac{1}{100}\)

=-8+1

=-7

\(A=-\dfrac{1}{6}-\left[\dfrac{9}{16}-\dfrac{9}{8}+\dfrac{3}{4}\right]\)

\(=\dfrac{-1}{6}-\dfrac{9-18+12}{16}=\dfrac{-1}{6}-\dfrac{3}{16}\)

\(=\dfrac{-8}{48}-\dfrac{9}{48}=-\dfrac{17}{48}\)

\(B=\left(-\dfrac{3}{4}+\dfrac{3}{4}\right)^2+\dfrac{3}{4}\cdot\dfrac{-5}{9}+7^3\)

=-15/36+343

=343-5/12=4111/12

Số số hạng của dãy là :  ( số )

 Có  ( cặp )

`1-5+9-13+...+393-397`

`=(1-5)+(9-13)+...+(393-397)` (197 cặp)

`=(-4)+(-4)+...+(-4)` 

`=(-4) xx 197`

`=-788`

1-5+9-13+...+393-397

=(-4)+(-4)+...+(-4)

=(-4)*100

=-400

\(\dfrac{\dfrac{5}{3}-\dfrac{5}{7}+\dfrac{5}{9}}{\dfrac{10}{3}-\dfrac{10}{7}+\dfrac{10}{9}}=\dfrac{5\left(\dfrac{1}{3}-\dfrac{1}{7}+\dfrac{1}{9}\right)}{10\left(\dfrac{1}{3}-\dfrac{1}{7}+\dfrac{1}{9}\right)}=\dfrac{1}{2}\)