x + 11 = 16
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(A=\dfrac{1}{5}\left(\dfrac{1}{6}-\dfrac{1}{11}+\dfrac{1}{11}-\dfrac{1}{16}+...+\dfrac{1}{496}-\dfrac{1}{501}\right)\)
\(=\dfrac{1}{5}\cdot\dfrac{55}{334}=\dfrac{11}{334}\)
\(B=1-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{5}+...+\dfrac{1}{19}-\dfrac{1}{21}=\dfrac{20}{21}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
(3 x 4 x 2 mũ 16) mũ 2 : ( 11 x 2 mũ 13 x 4 mũ 11 - 16 mũ 9 )
= 2
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(\dfrac{7}{9}\times\dfrac{13}{25}\times\dfrac{9}{7}=\left(\dfrac{7}{9}\times\dfrac{9}{7}\right)\times\dfrac{13}{25}=1\times\dfrac{13}{25}=\dfrac{13}{25}\)
b) \(\dfrac{5}{9}\times\dfrac{21}{25}+\dfrac{21}{25}\times\dfrac{4}{9}\)
\(=\dfrac{21}{25}\times\left(\dfrac{5}{9}+\dfrac{4}{9}\right)\)
\(=\dfrac{21}{25}\times1=\dfrac{21}{25}\)
c) \(\dfrac{19}{5}\times\dfrac{11}{16}-\dfrac{9}{5}\times\dfrac{11}{16}\)
\(=\dfrac{11}{16}\times\left(\dfrac{19}{5}-\dfrac{9}{5}\right)\)
\(=\dfrac{11}{16}\times2=\dfrac{22}{16}=\dfrac{11}{8}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
em ghi rõ cộng trừ nhân chia đi em
chị thấy đề lạ quá '* ' cái này lf cái j vậy em
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
2/5 + 11/15 = 17/15
7/8 - 7/9 = 7/72
11/13 x 26/31 = 22/31
16/24 : 4 = 1/6
30 : 6/5 = 25
9/16 : 4 = 9/64
1/2 : 1/3 x 8/15 = 3/2 x 8/15 = 4/5
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(C=\frac{1}{1.6}+\frac{1}{6.11}+\frac{1}{11.16}+...+\frac{1}{2011.2016}\)
\(5C=\frac{5}{1.6}+\frac{5}{6.11}+\frac{5}{11.16}+...+\frac{5}{2011.2016}\)
\(5C=1-\frac{1}{6}+\frac{1}{6}-\frac{1}{11}+\frac{1}{11}-\frac{1}{16}+...+\frac{1}{2011}-\frac{1}{2016}\)
\(5C=1-\frac{1}{2016}\)
\(5C=\frac{2015}{2016}\)
\(C=\frac{2015}{2016}:5\)
\(C=\frac{403}{2016}\)
Đặt A = \(\frac{1}{1\times6}+\frac{1}{6\times11}+\frac{1}{11\times16}+...+\frac{1}{2011\times2016}\)
\(A\times5=\frac{5}{1\times6}+\frac{5}{6\times11}+\frac{5}{11\times16}+...+\frac{5}{2011\times2016}\)
\(A\times5=\frac{1}{1}-\frac{1}{6}+\frac{1}{6}-\frac{1}{11}+\frac{1}{11}-\frac{1}{16}+...+\frac{1}{2011}-\frac{1}{2016}\)
\(A\times5=\frac{1}{1}-\frac{1}{2016}\)
\(A=\frac{2015}{2016}\times\frac{1}{5}\)
\(A=\frac{2015}{10080}=\frac{403}{2016}\)
x+11=16
x=16-11
x=5![[IMG]](http://data.kenhsinhvien.net/upload/files/1207/KenhSinhVien.Net-tumblr-m4bphxqrv71rpir0bo1-500.gif)
100% là đúng,
x + 11 = 16
x = 16 - 11
x = 5