a) \(85^2-15^2=\left(85-15\right)\left(85+15\right)=70.100=7000\)

b) \(93^3+21.93^2+3.49.93+343\)

\(=93^3+3.7.93^2+3.7^2.93+7^3\)

\(=\left(93+7\right)^3\)

\(=100^3=1000000\)

c) \(73^2-13^2-10^2+20.13\)

\(=73^2-\left(13^2+10^2-20.13\right)\)

\(=73^2-\left(13-10\right)^2\)

\(=73^2-3^2\)

\(=\left(73+3\right)\left(73-3\right)\)

\(=76.70=5320\)

d) Viết = Latex hộ mình

a) Ta có: \(85^2-15^2\)

\(=\left(85-15\right)\left(85+15\right)\)

\(=70\cdot100=7000\)

b) Ta có: \(93^3+21\cdot93^2+3\cdot49\cdot93+343\)

\(=93^3+3\cdot93^2\cdot7+3\cdot93+7^2+7^3\)

\(=\left(93+7\right)^3\)

\(=100^3=1000000\)

c) Ta có: \(73^2-13^2-10^2+20\cdot13\)

\(=73^2-\left(13^2+10^2-20\cdot13\right)\)

\(=73^2-\left(13^2-2\cdot13\cdot10+10^2\right)\)

\(=73^2-\left(13-10\right)^2\)

\(=73^2-3^2=\left(73-3\right)\left(73+3\right)\)

\(=70\cdot76=5320\)

A = 4 . 2 . 25 . 5 . 175 

A = 2² . 2 . 5² . 5 . 5² . 7 

A = 2²⁺¹ . 5²⁺¹⁺² . 7  

A = 2³ . 5⁵ .7

A = 175000

\(B=4^2-10^4:\left(50\cdot273-50\cdot73\right)\)

\(B=4^2-10^4:\left[50\cdot\left(273-73\right)\right]\)

\(B=4^2-10^4:\left(50\cdot200\right)\)

\(B=4^2-10^4:10^4=4^2-1=15\)

\(C=3\times53\times6+2\times9\times87-18\times40\)

\(C=18\times53+18\times87-18\times40\)

\(C=18\times\left(53+87-40\right)\)

\(C=18\times100=1800\)

Cau 1)

21+(x+23)=50

X+23=50-21

X=29-23

X=6

Cau 2)

125+(x-100)=150

X-100=150-125

X=25+100

X=125

Cau 3)

24+(10-x)=26

10-x=26-24

X=10-2

X=8

1. -86 + ( -14)

= -86 - 14

= -100

2. 123 + ( -36)

= 123 - 36

= 87

3. ( -44) - ( -66)

= -44 + 66

= 22

4. -82 + (-28)

= -82 - 28

= -110

5. 83 + ( -17)

= 83 - 17

= 66

Các bài khác làm tương tự nha bạn

1/ (-86)+(-14)=-86-14=-100

2/123+(-36)=123-36=87

3/(-44)-(-66)=-44+66=22

4/-82+(-28)=-82-28=-110

5/83+(-17)=83-17=66

6/(-83)-33=(-83)+(-33)=-116

7/ 73+(-24)=73-24=49

8/84+(-48)=84-48=36

9/-72-82=-72+(-82)=-154

10/-97-82=-97+(-82)=-179

11/19+(-92)=19-92=-73

12/38-28=10

13/13+(-27)=13-27=-14

14/-85+29=-85-(-29)=-114

15/-84-(-27)=-84+27=-57

16/-23+78=-23-(-78)=-101

17/93+(-29)=93-29=64

18/-74-83=-74+(-83)=-157

19/-183+83=-183-(-83)=-266

20/849-(-3832)=849+3832=4681

Có gì sai mong bạn sửa giúp mình nhé!

ối dồi ôi nhiều thế

mk chịu

đề là gì vậy bạn

1/ -100

2/ 77

3/ 22

4/ 110

5/66

6/-116

7/49

8/36

Nốt câu c

\(C=\frac{97^3+83^3}{180}-97.83\)

\(=\frac{\left(97+83\right)\left(97^2-97.83+83^3\right)}{180}-97.83\)

\(=\frac{180.\left(97^2-97.83+83^2\right)}{180}-97.83\)

\(=97^2-97.83+83^2-97.83\)

\(=\left(97-83\right)^2=14^2=196\)

1.

a) \(2\left(x+3\right)-x^2-3x=0\)

⇔ \(2\left(x+3\right)-x\left(x+3\right)=0\)

⇔ \(\left(x+3\right)\left(2-x\right)=0\)

⇔ \(\left[{}\begin{matrix}x=2\\x=-3\end{matrix}\right.\)

b) \(\left(2x+1\right)^2-\left(x-1\right)^2=0\)

⇔ \(\left(2x+1-x+1\right)\left(2x+1+x-1\right)=0\)

⇔ \(3x\left(x+2\right)=0\)

⇔ \(\left[{}\begin{matrix}x=0\\x=-2\end{matrix}\right.\)

c) \(x^2-4x+3=0\)

⇔ \(x\left(x-1\right)-3\left(x-1\right)=0\)

⇔ \(\left(x-1\right)\left(x-3\right)=0\)

⇔ \(\left[{}\begin{matrix}x=1\\x=3\end{matrix}\right.\)

2, a) \(B=\left(2x+3\right)\left(4x^2-6x+9\right)-2\left(4x^3-1\right)-2x\)

⇔ \(B=8x^3+27-8x^3+2-2x=29-2x\)

Tại x = 3

Thì B = 29 - 6 = 23

các bn lm đến đâu cx dc miễn là lm hộ mk cái ạ, ai đang lm vào nhắn tin vs mk để mk bít nha

a; \(-\dfrac{8}{3}+\dfrac{7}{5}-\dfrac{71}{15}< x< -\dfrac{13}{7}+\dfrac{19}{14}-\dfrac{7}{2}\)

              -\(\dfrac{19}{15}\) - \(\dfrac{71}{15}\) < \(x\) < -\(\dfrac{1}{2}\) - \(\dfrac{7}{2}\)

              -6 < \(x\) < -4

             vì \(x\) \(\in\) Z nên \(x\) = -5

- \(\dfrac{19}{6}+\dfrac{-15}{2}+\dfrac{11}{3}\) < \(x\) < - \(\dfrac{5}{4}\) + \(\dfrac{19}{12}\) - \(\dfrac{10}{3}\)

- \(\dfrac{32}{3}+\dfrac{11}{3}< x< \) \(\dfrac{1}{3}\) - \(\dfrac{10}{3}\)

-7 < \(x\) < - 3

Vì \(x\in\) Z nên \(x\in\) {-6;-5;-4}