giúp mình với mình cần gấp

ta có 2n+3=n+n+3=(n+1)+(n+1)+1     nhớ k nhé mọi người     pls

ta có n+1 chia hết cho n+1

=>1 chia hết cho n+1=>n+1 thuộc U(1)=+-1

=>n+1=1=>n=0;n+1=-1=>n=-2

vậy n=0 hoặc n=-2

giúp mk với

Theo mk b lên h.com để đc giải đáp tốt hơn nhé!

#chanh

\(3\times\left(\frac{1}{5\times8}+\frac{1}{8\times11}+....+\frac{1}{97\times100}+x\right)=\frac{319}{100}\)

\(\Rightarrow\left(\frac{3}{5\times8}+\frac{3}{8\times11}+\frac{3}{11\times14}+...+\frac{3}{97\times100}\right)+3\times x=\frac{319}{100}\)

\(\Rightarrow\frac{1}{5}-\frac{1}{8}+\frac{1}{8}-\frac{1}{11}+\frac{1}{11}-\frac{1}{14}+...+\frac{1}{97}-\frac{1}{100}+3\times x=\frac{319}{100}\)

\(\Rightarrow\frac{1}{5}-\frac{1}{100}+3\times x=\frac{319}{100}\)

\(\Rightarrow\frac{19}{100}+3\times x=\frac{319}{100}\)

\(\Rightarrow3\times x=\frac{319}{100}-\frac{19}{100}\)

\(\Rightarrow3\times x=3\)

\(\Rightarrow x=3:3\)

\(\Rightarrow x=1\)

Vậy x = 1

= \(\left(\frac{37}{7}+\frac{58}{7}-\frac{327}{7}\right)x\left(\frac{8}{11}+\frac{5}{11}-\frac{2}{11}\right)\)

= \(\left(\frac{-232}{7}\right)x\left(1\right)\)

= \(\frac{-232}{7}\)

=5^14.3:5^13+5^13:5^13                    nho k de mik co nang luong giup moi nguoi nhe ban

=15+1

=16

5)

để \(\frac{5x-3}{x+1}\)là số nguyên

\(5x-3⋮x+1\)

\(x+1⋮x+1\)

\(\Rightarrow5\left(x+1\right)⋮x+1\)

\(5x-3-\left(5x-5\right)⋮x+1\)

\(-2⋮x+1\)

\(\Rightarrow x+1\inƯ\left(2\right)=\left\{\pm1;\pm2\right\}\)

Vậy \(x\in\left\{0;-2;1;-3\right\}\)

\(-125\%\cdot\frac{7}{3}\cdot\left(\frac{-9}{7}\right)+0,25:\frac{4}{16}\)

\(=\frac{-5}{4}\cdot\frac{7}{3}\cdot\left(\frac{-9}{7}\right)+\frac{1}{4}:\frac{1}{4}\)

\(=\frac{15}{4}+1=\frac{19}{4}\)

4/5.17/3-4/3:5/57=-14.9421018698

=4/5.17/3-4/3.57/5

=68/15-228/15

=-160/15

=-32/3

\(\frac{\left(2^3.5.7\right).\left(5^2.7^3\right)}{\left(2.5.7^2\right)^2}\)
\(=\frac{\left(8.5.7\right).\left(25.7^3\right)}{4.25.7^4}\)
\(=\frac{280.25.7^3}{4.25.7^4}\)
\(=\frac{280}{4.7}\)
\(=\frac{280}{28}=10\)