a) \(\overline{X}=\dfrac{6.5+7.8+8.4+9.2+10}{5+8+4+2+1}=7,3\)

\(n=20\Rightarrow\dfrac{n}{2}=10\)

\(\Rightarrow Q_2=7\)

\(\dfrac{n}{4}=5\Rightarrow Q_1=6\)

\(\dfrac{3n}{4}=15\Rightarrow Q_3=8\)

\(m_0=7\)

b) \(\overline{X}=\dfrac{26.10+27.8+28.4+29.2+30}{10+8+4+2+1}=27,04\)

\(n=25\Rightarrow\dfrac{n}{4}=6,25\Rightarrow Q_1=26\)

\(\dfrac{n}{2}=12,5\Rightarrow Q_2=27\)

\(\dfrac{3n}{4}=18,75\Rightarrow Q_3=28\)

\(m_0=26\)

Vt lại đề rõ bằng latex đi bạn

Trong \(\Delta ADC\) có \(K;I;B\) thẳng hàng

\(\Rightarrow\dfrac{AK}{CK}.\dfrac{ID}{AI}.\dfrac{BC}{BD}=1\)

\(\Rightarrow\dfrac{AK}{CK}.\dfrac{1}{4}.\dfrac{6}{5}=1\)

\(\Rightarrow\dfrac{AK}{CK}=\dfrac{10}{3}\Rightarrow\dfrac{CK}{AK}=\dfrac{3}{10}=0,3\)

\(\Rightarrow\overrightarrow{CK}=-0,3\overrightarrow{AK}\)

\(\Rightarrow m=-0,3\)

a)

\(nNAOH=nH_2SO_4=\dfrac{4,9}{98}=0,05\left(mol\right)\)

\(nNaOH=0,05.4=2\left(g\right)\)

b)

\(nN_2=nO_2=\dfrac{1,6}{32}=0,05\left(mol\right)\)

\(mN_2=0,05.28=1,4\left(g\right)\)

\(n_{RO_2}=\dfrac{V}{22,4}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\)

\(\Rightarrow M_{RO_2}=\dfrac{m}{n}=\dfrac{16}{0,25}=64\) (g/mol)

\(\Rightarrow M_R+2M_O=64\)

\(\Rightarrow M_R=64-2.16=32\left(S\right)\)

\(\Rightarrow\)R là S

\(\Rightarrow\)B là SO₂

Câu 1:B

\(\dfrac{x^2-xy}{3y^2-3xy}\)

\(=\dfrac{x\left(x-y\right)}{3y\left(y-x\right)}\)

\(=-\dfrac{x\left(x-y\right)}{3y\left(x-y\right)}\)

\(=-\dfrac{x}{3y}\)

Câu 3:A

\(\dfrac{5x^2y-5xy}{x^2-2x+1}\)

\(=\dfrac{5xy\left(x-1\right)}{\left(x-1\right)^2}\)

\(=\dfrac{5xy}{x-1}\)

\(B=2018-\dfrac{1}{2}\left(1+2\right)-\dfrac{1}{3}\left(1+2+3\right)-\dfrac{1}{4}\left(1+2+3+4\right)-...-\dfrac{1}{2017}\left(1+2+3+...+2017\right)\)

\(B=2018-\dfrac{2+1}{2}-\dfrac{3+1}{2}-\dfrac{4+1}{2}-...-\dfrac{2017+1}{2}\)

\(B=2018-\dfrac{3}{2}-\dfrac{4}{2}-\dfrac{5}{2}-...-\dfrac{2018}{2}\)

\(B=2018-\dfrac{3+4+5+...+2018}{2}\)

\(B=2018-\dfrac{\left(2018+3\right)\left(2018-3+1\right)}{2}:2\)

\(B=2018-\dfrac{2021.2016}{2}:2\)

\(B=2018-2021.1008:2\)

\(B=2018-1018584\)

\(B=-1016566\)

`b)`

Tiệm cận đứng là:

`x^2 -4x=0=>x=0` hoặc `x=4`

Tiệm cận ngang là:

`y=0`

Tiệm cận xiên là ko có

`b)`

Không có tiệm cận ngang

Tiệm cận đứng là:

TXĐ:\(D=R\backslash\left\{2\right\}\)

Thay `x=2` vào tử số ta được `9 ne 0` (luôn đúng)

`=>x=2`

Tiệm cận xiên là:

\(y=\dfrac{3x^2-2x+1}{2-x}=-3x-4+\dfrac{9}{-x+2}\)

`=>y=-3x-4`

`a)`

Tiệm cận đứng là:`x-3=0=>x=3`

Không có tiệm cận ngang 

Tiệm cận xiên là:

\(\dfrac{2x^2}{x-3}=2x+6+\dfrac{18}{x-3}\)

`=>y=2x+6`