\(A=\frac{1}{4}:\left(10,3-9,8\right)-\frac{3}{4}\)

\(A=\frac{1}{4}:\left(0,5\right)-\frac{3}{4}\)

\(A=\frac{1}{4}:\frac{1}{2}-\frac{3}{4}\)

\(A=\frac{1}{4}\cdot2-\frac{3}{4}=\frac{1}{2}-\frac{3}{4}=\frac{2}{4}-\frac{3}{4}=\frac{-1}{4}\)

Bài 1:

a, \(A=\frac{1}{4}:0,5-\frac{3}{4}\)

       \(=\frac{1}{2}-\frac{3}{4}\)

         \(=\frac{-1}{4}\)

b, \(B=\frac{6}{7}+\frac{5}{8}:5-\frac{3}{16}.\left(-2\right)^2\)

       \(=\frac{6}{7}+\frac{1}{8}-\frac{3}{4}\)

       \(=\frac{6}{7}+\frac{-5}{8}\)

       \(=\frac{13}{56}\)

Hk tốt

1. Is that your room ?                                                                 1. Is this her flower garden ?

2. Is that her hat ?                                                                       2. Is this their house ?

3. Is that his bike ?                                                                     3. Is this his cat ?

4. Is that their dog ?                                                                   4. Is this your pen ?

5. Is that your car ?                                                                    5. Is this her pencil case ?

Trả lời: mk k bít

Ukm k sao đâu, mk cũng từ nghĩ ra cách làm rồi

\(34\%:\frac{51}{16}-\frac{34}{9}:6,5-\left(0,4\right)^2\)

\(=\frac{34}{100}:\frac{51}{16}-\frac{34}{9}:\frac{65}{10}-0,16\)

\(=\frac{34\cdot16}{100\cdot51}-\frac{34\cdot10}{9\cdot65}-\frac{16}{100}\)

\(=\frac{2\cdot17\cdot4\cdot4}{4\cdot5\cdot5\cdot17\cdot3}-\frac{2\cdot17\cdot2\cdot5}{3\cdot3\cdot5\cdot13}-\frac{4}{25}\)

\(=\frac{8}{75}-\frac{34}{117}-\frac{4}{25}=\left(\frac{8}{75}-\frac{4}{25}\right)-\frac{34}{117}\)

\(=\left(\frac{8}{75}-\frac{12}{75}\right)-\frac{34}{117}=\frac{-4}{75}-\frac{34}{117}\)

\(34\%\div\frac{51}{16}-\frac{34}{9}\div\frac{6}{5}-\left(0,4\right)^2\)

\(=\frac{34}{100}\times\frac{16}{51}-\frac{34}{9}\times\frac{5}{6}-0,16\)

\(=\frac{17}{50}\times\frac{16}{51}-\frac{85}{27}-\frac{16}{100}\)

\(=\frac{8}{75}-\frac{85}{27}-\frac{4}{25}\)

\(=\frac{8}{75}-\frac{85}{27}-\frac{12}{75}\)

\(=\frac{-4}{75}-\frac{85}{27}\)

\(=\frac{-108}{2025}-\frac{6375}{2025}\)

\(=\frac{-6483}{2025}\)

b)\(\frac{2n+6}{n-2}=\frac{2n-4+10}{n-2}=2+\frac{10}{n-2}\)

\(\Rightarrow n-2\in U\left(10\right)=\left\{1;2;5;10\right\}\)

\(\Rightarrow n=\left\{3;4;7;12\right\}\)

ý a thì tớ ko biết ý b thì làm như sau

2[n-2]+4+6

2[n-2]+10

n-2/n-2

10/[n-2]

Ư[10]=[1,-1,2,-2,5,-5,10,-10]

vì n-2 thuộc Ư[10]=[3,1,4,0,7,-3,12,-8]

[3,1,4,0,7,-3,12,-8] đó là kết quả chúcbanjk học tốt

NHỚ NHA

Ta có: \(\frac{6n+3}{3n+6}=\frac{6n+12-9}{3n+6}=\frac{2\left(6n+3\right)-9}{3n+6}=2-\frac{9}{3n+6}\)

Để 6n+3 chia hết cho 3n+6. thì 9 chia hết cho 3n+6

=> 3n+6\(\in\)Ư(9)

=> 3n+6 \(\in\){1,3,9}

=> 3n = 3

=> n = 3:3

=> n = 1

(1x1/2)x(1x1/3)x(1x1/4)...(1x1/2007)

=1/2x1/3x1/4...1/2007

=1/(2x3x4...2007)

=???

\(\frac{3}{4}+\frac{1}{4}:x=\frac{1}{2}\)

           \(\frac{1}{4}:x=\frac{1}{2}-\frac{3}{4}\)

           \(\frac{1}{4}:x=-\frac{1}{4}\)

                 \(x=\frac{1}{4}:\left(-\frac{1}{4}\right)\)

                 \(x=-1\)

~Học tốt~

\(\frac{3}{4}+\frac{1}{4}:x=\frac{1}{2}\)

\(\frac{1}{4}:x=\frac{1}{2}-\frac{3}{4}\)

\(\frac{1}{4}:x=\frac{-1}{4}\)

\(x=\frac{1}{4}:\frac{-1}{4}\)

\(x=-1\)

Gọi phân số đó là \(\frac{a}{9}\)

Ta có : 

\(\Rightarrow\frac{a+10}{27}=\frac{3a}{27}\)

\(\Rightarrow\)a + 10 = 3a

\(\Rightarrow\) 3a - a = 10

\(\Rightarrow\)2a = 10

\(\Rightarrow\)a = 5

Vậy phân số cần tìm là \(\frac{5}{9}\)