=5079275

tính hẳn ra hộ em là đầu tiên phải làm như nào rồi thế nào được không ạ !

- _ -

\(=15\times''3+2+5''\) \(-100\)

\(=15\times10-100\) 

\(=50\) 

Lưu ý ; Dấu ngoặc kép thay cho dấu ngoặc đơn nha 

Chúc em học giỏi và gặt hái được nhiều kết quả cao

\(\dfrac{x}{a}=\dfrac{m-\dfrac{x}{2}}{m}\) 

\(\Rightarrow xm=a\left(m-\dfrac{x}{2}\right)\)

\(\Rightarrow xm=am-\dfrac{ax}{2}\)

\(\Rightarrow2xm=2am-ax\)

\(\Rightarrow2xm+ax=2am\)

\(\Rightarrow x\left(2m+a\right)=2am\)

\(\Rightarrow x=\dfrac{2am}{a+2m}\)

vâng em cảm ơn ạ

ta có: \(\left(3x-5\right)^2+\left(2-x\right)^3+\left(3-2x\right)^3=0\)

<=>\(\left(5-3x\right)^2+\left(2-x+3-2x\right)\left[\left(2-x\right)^2+\left(2-x\right)\left(3-2x\right)+\left(3-2x\right)^2\right]=0\)

<=>\(\left(5-3x\right)^2+\left(5-3x\right)\left(4-4x+x^2-6+7x-2x^2+9-12x+4x^2\right)=0\)

<=>\(\left(5-3x\right)^{^2}+\left(5-3x\right)\left(7-9x-3x^2\right)=0\)

<=>\(\left(5-3x\right)\left(5-3x+7-9x-3x^2\right)=0\)

<=>\(3.\left(5-3x\right)\left(4-4x-x^2\right)=0\)

Mà 4-4x-x^2>0 nên 5-3x=0 <=>x=5/3

8,75xy+1,25xy=20
xy(8,75+1,25)=20
10xy=20
xy=20:10
xy=2
Ta có 2=2.1 nên
x=1:y=2 hoặc x=2; y=1

Nhớ tick!! then kiu!!

WTF CỘNG RỒI NHÂN Y ????? GHI ĐỀ SAI R BẠN EI

ko 1 y thôi nha mấy bạn ơi

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

\(=x^2\left(x-1\right)+3\left(x-1\right)\)

\(=\left(x^2+3\right)\left(x-1\right)\)

Để \(f\left(x\right)>0\Leftrightarrow\left(x^2+3\right)\left(x-1\right)>0\)

Mà \(x^2\ge0\forall x\Leftrightarrow x^2+3>0\)

\(\Rightarrow x-1>0\Leftrightarrow x=1\)

\(h\left(x\right)=4x^3-14x^2+6x-21< 0\)

\(\Leftrightarrow0\left(x-\frac{7}{2}\right)\left(4x^2+6\right)< 0\)

Mà \(4x^2+6>0\forall x\Leftrightarrow h\left(x\right)< 0\Leftrightarrow x-\frac{7}{2}< 0\Leftrightarrow x< \frac{7}{2}\)

f(x)=x3−x2+3x−3f(x)=x3−x2+3x−3

=x2(x−1)+3(x−1)=x2(x−1)+3(x−1)

=(x2+3)(x−1)=(x2+3)(x−1)

Để f(x)>0⇔(x2+3)(x−1)>0f(x)>0⇔(x2+3)(x−1)>0

Mà x2≥0∀x⇔x2+3>0x2≥0∀x⇔x2+3>0

⇒x−1>0⇔x=1⇒x−1>0⇔x=1

h(x)=4x3−14x2+6x−21<0h(x)=4x3−14x2+6x−21<0

⇔0(x−72)(4x2+6)<0⇔0(x−72)(4x2+6)<0

Mà 4x2+6>0∀x⇔h(x)<0⇔x−72<0⇔x<72

chịu rồi xin lỗi bạn nha

sao khó vậy tù rôi mình làm cho

xin lôi mình chưa sang cấp 2 nhưng mình biết sơ sơ

One more summer to come. It won't be the same as the year before I go home. This year will be an interesting break with those delivered from my friend. We have put together a schedule. The first destination is Da Nang. we will stay there for about 4 days. Go BA NA Hills and some other places. Then on to nha trang. And the last stop is in Dalat. I think it is interesting and will certainly have a lot of memories. We will take a lot of pictures, enjoy the many delicacies and buy lots of souvenirs.Just thoughtit was funny thíhc. I hope ngỉwill take place during the fun and convenient.2. Da Lat city is located in the center of the southern highlands. Da Lat city is famous as a cool, verdant environment as a park. You can stroll through the old French villas with magnificent, visit Bao Dai palace -summer residence of the last emperor -are imposing on a hill or valley to explore the full poem Love dream within a 5km from the city center to the north. Dalat is famous for the unique cafe and is a special favorite with tourists in the country and the couple went on their honeymoon.

Dalat is being the flower city. There have many flowers and the weather is cool. Dalat is famous for many beauty sport and fog. When you visit to Dalat you will fell comfortable. You should get up early at 5.00am that can go for a walk along Xuan Huong lake, and enjoy fresh air. You can go to the market buy some special-food such as strowbery, atiso, tea, coffee, souvenir or go shopping. If you are interested sightseeing you can visit to vallay of love, Mong Mo hill, Tuyen Lam lake, Than tho lake, Datala fallwater....etc.  At night, you can go drink coffe in center city.On night Saturday and Sunday, you can come Hoa binh street where you can enjoy the foods in night market bean milks, egg, arca and baked snail or buy something.

a) 40 và 60
Ta có Ư(40)\(\in\){1;2;4;5;6;8;10;16;20}
          Ư(60)\(\in\){1;2;3;4;5;6;10;12;15;20;30)
     ƯC(40;60)\(\in\){1;2;3;4;5;6;10;20}
Trong đó,20 là ƯCLN.Vậy ƯCLN(40;60)\(\in\){20}
b)