1. Tìm x
a) 3,2. x + (-12).x + 2,7 = -4,9
b) -5,6.x + 2,9.x -3,86= -9,8
2. tính Giá trị
A= -5,13:\(\left(5\dfrac{5}{28}-1\dfrac{8}{9}.1.25+1\dfrac{16}{63}\right)\)
B= \(\left(3\dfrac{1}{3}.1,9+19,5:4\dfrac{1}{3}\right).\left(\dfrac{62}{75}-\dfrac{4}{25}\right).\)
tìm số nguyen x: \(\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}+...+\dfrac{1}{x}=\dfrac{1023}{1024}\)
Choose the words or phrases that are not correct in Standard English.
1. \(\dfrac{At}{A}\) present, he \(\dfrac{talks}{B}\) to \(\dfrac{his}{C}\) friends \(\dfrac{about}{D}\) their new stamp.
2. \(\dfrac{Her}{A}\) best friend \(\dfrac{lives}{B}\) \(\dfrac{in}{C}\) Ha Noi, the capital \(\dfrac{in}{D}\) Viet Nam.
3. \(\dfrac{In}{A}\) Electronics class, he learns \(\dfrac{what}{B}\) to \(\dfrac{repair}{C}\) \(\dfrac{household}{D}\) appliances.
4. \(\dfrac{Their}{A}\) \(\dfrac{teacher}{B}\) asks them \(\dfrac{do}{C}\) \(\dfrac{many}{D}\) experiment.
5. They \(\dfrac{are}{A}\) working \(\dfrac{at}{B}\) \(\dfrac{neighborhood}{C}\) clean-up \(\dfrac{campaigns}{D}\) .
Choose the words or phrases that are not correct in Standard English.
1. There \(\dfrac{are}{A}\) a large, \(\dfrac{modern}{B}\) bathroom \(\dfrac{and}{C}\) a kitchen \(\dfrac{in}{D}\) the apartment.
2. He thanks \(\dfrac{her}{A}\) \(\dfrac{about}{B}\) invitting \(\dfrac{him}{C}\) \(\dfrac{to}{D}\) the party.
cho hình vuông ABCD .Qua điểm A vẽ một đường thẳng cắt cạnh BC tại E và cắt đường thẳng CD tại F.CMR
\(\dfrac{1}{AB^2}=\dfrac{1}{AB^2}+\dfrac{1}{ÀF^2}\)
Tìm các giá trị nguyên của x để \(A=1-\dfrac{3}{\sqrt{x}+1}\)nhận các giá trị nguyên.
Cho :
\(\dfrac{bz-cy}{a}=\dfrac{cx-az}{b}=\dfrac{ay-bx}{c}\)
\(CMR:\dfrac{x}{a}=\dfrac{y}{b}=\dfrac{z}{c}\left(a,b,c\ne\right)\)
giúp mk
Error Identification.
1.\(\dfrac{\text{Jean}}{ }\) cloth \(\dfrac{was}{ }\) made \(\dfrac{\text{complete}}{ }\) \(\dfrac{\text{from}}{ }\) cotton.
2.\(\dfrac{\text{Would}}{ }\) you like \(\dfrac{\text{come}}{ }\) and \(\dfrac{\text{visit}}{ }\) me \(\dfrac{\text{next}}{ }\) summer?
3.Ao Dai \(\dfrac{\text{was}}{ }\) \(\dfrac{\text{frequently}}{ }\) worn by both \(\dfrac{\text{man}}{ }\) and \(\dfrac{\text{women}}{ }\).
4.\(\dfrac{\text{Wearing uniforms}}{ }\) \(\dfrac{\text{help}}{ }\) students \(\dfrac{\text{feel}}{ }\) equal in many \(\dfrac{\text{ways}}{ }\).
5.\(\dfrac{\text{Wearing}}{ }\) uniforms \(\dfrac{\text{encourages}}{ }\) students \(\dfrac{\text{to be}}{ }\) proud \(\dfrac{\text{about}}{ }\) their school.
6.She \(\dfrac{\text{wishes}}{ }\) she \(\dfrac{\text{can}}{ }\) speak English as \(\dfrac{\text{well}}{ }\) \(\dfrac{\text{as}}{ }\) her teacher.
7.I seldom \(\dfrac{\text{go}}{ }\) to \(\dfrac{\text{a}}{ }\) football match.I'm not very \(\dfrac{\text{interesting}}{ }\) \(\dfrac{\text{in}}{ }\) football.
8.A \(\dfrac{\text{new}}{ }\) style of jeans \(\dfrac{\text{have}}{ }\) just been \(\dfrac{\text{introduced}}{ }\) \(\dfrac{\text{in }}{ }\)the USA.
9.\(\dfrac{\text{In}}{ }\) the \(^{18^{th}}\)century, jean cloth \(\dfrac{\text{was}}{ }\) made \(\dfrac{\text{completely}}{ }\) \(\dfrac{\text{by}}{ }\) cotton.
10.Mr.Brown is \(\dfrac{\text{interested}}{ }\) in \(\dfrac{\text{to go shopping}}{ }\) \(\dfrac{\text{every}}{ }\) Sunday.
11.I \(\dfrac{\text{wish}}{ }\) I \(\dfrac{\text{have}}{ }\) a new watch. \(\dfrac{\text{Mine}}{ }\) is \(\dfrac{\text{too }}{ }\)old.
12.Emma \(\dfrac{\text{used to}}{ }\) lie \(\dfrac{\text{on}}{ }\) the beach when she \(\dfrac{\text{lives}}{ }\) \(\dfrac{\text{by the sea}}{ }\).
13.\(\dfrac{\text{Wearing}}{ }\) uniforms \(\dfrac{\text{encourage}}{ }\) the students \(\dfrac{\text{to be}}{ }\) proud of \(\dfrac{\text{their}}{ }\) schools.
14.How \(\dfrac{\text{long}}{ }\) \(\dfrac{\text{have}}{ }\) you \(\dfrac{\text{learning}}{ }\) \(\dfrac{\text{English}}{ }\)?
15.Ao dai \(\dfrac{\text{was}}{ }\) \(\dfrac{\text{frequent}}{ }\) \(\dfrac{\text{worn }}{ }\)by \(\dfrac{\text{both men and women}}{ }\).
Tìm 2 số nguyên dương nhỉ nhất a;b biết \(\dfrac{a}{b}\)= \(\dfrac{18}{27}\) và UCLN (a;b) =17
Làm nhanh giúp mk nhé, trình bày rõ ràng giúp mk