Ta có: \(A=\frac{19^5+2016}{19^5-1}=\frac{19^5-1+2017}{19^5-1}=\frac{19^5-1}{19^5-1}+\frac{2017}{19^5-1}=1+\frac{2017}{19^5-1}\)

\(B=\frac{19^5+2015}{19^5-2}=\frac{19^5-2+2017}{19^5-2}=\frac{19^5-2}{19^5-2}+\frac{2017}{19^5-2}=1+\frac{2017}{19^5-2}\)

Vì \(\frac{2017}{19^5-1}< \frac{2017}{19^5-2}\Rightarrow1+\frac{2017}{19^5-1}< 1+\frac{2017}{19^5-2}\Rightarrow A< B\)

Vậy A < B

Ta có: \(A=\dfrac{19^5+2016}{19^5-1}=1+\dfrac{2017}{19^5-1}\)

\(B=\dfrac{19^5+2015}{19^5-2}=1+\dfrac{2017}{19^5-2}\)

Vì \(\dfrac{2017}{19^5-1}< \dfrac{2017}{19^5-2}\Rightarrow1+\dfrac{2017}{19^5-1}< 1+\dfrac{2017}{19^5-2}\)

\(\Rightarrow A< B\)

Vậy A < B

A < B

\(A< B\)

\(A=\frac{19^5-1+2017}{19^5-1}=1+\frac{2017}{19^5-1}\)

\(B=\frac{19^5+2015}{19^5-2}=\frac{19^5-2+2017}{19^5-2}=1+\frac{2017}{19^5-2}\)
\(\Rightarrow1+\frac{2017}{19^5-1}< 1+\frac{2017}{19^5-2}\)
\(\Rightarrow A< B\)

ta thấy:B>1

=>\(B=\frac{19^5+2015}{19^5-2}>\frac{19^5+2015+1}{19^5-2+1}=\frac{19^5+2016}{19^5-1}=A\Rightarrow B>A\)

vậy.....

LẤY (2015/19^5-1)-(2014/19^5-2)=(2015*19^5-2*2015-2014*19^5+2014)/((19^5-10*(19^5-2)

=(19^5-2016)/((19^5-1)*(19^5-2)>0

HAY A>B

phan conan ơi dấu sao là j

Nhân tích chéo 

mình chỉ gợi ý thôi bạn tự làm nhé

\(A=\frac{19^5-1+2017}{19^5-1}\)

\(A=1+\frac{2017}{19^5-1}\)

\(B=\frac{19^5+2015}{19^5-2}=\frac{19^5-2+2017}{19^5-2}=\frac{1+2017}{19^5-2}\)

\(\Rightarrow1+\frac{2017}{19^5-1}< 1+\frac{2017}{19^5-2}\)

\(\Rightarrow A< B\)

a) \(3\cdot24^{10}=3\cdot6^{10}\cdot4^{10}=3\cdot3^{10}\cdot2^{10}\cdot2^{20}\)

\(=3^{11}\cdot2^{30}\)

\(4^{30}=2^{30}\cdot2^{30}=2^{30}\cdot4^{15}\)

Ta có \(4^{15}>3^{15}>3^{11}\) nên \(4^{15}>3^{11}\)

Khi đó \(4^{15}\cdot2^{30}>3^{11}\cdot2^{30}\) hay \(4^{30}>3\cdot24^{10}\)

b) \(\dfrac{3}{1^2\cdot2^2}+\dfrac{5}{2^2\cdot3^2}+...+\dfrac{19}{9^2\cdot10^2}\)

\(=\dfrac{3}{1\cdot4}+\dfrac{5}{4\cdot9}+...+\dfrac{19}{81\cdot100}\)

\(=1-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{9}+...+\dfrac{1}{81}-\dfrac{1}{100}\)

\(=1-\dfrac{1}{100}=\dfrac{99}{100}< 1\)

Vậy dãy trên nhỏ hơn 1

a/

\(4^{30}=\left(2^2\right)^{30}=2^{60}=2^{30}.2^{30}=\left(2^2\right)^{15}.2^{30}=4^{15}.2^{30}\)

\(3.24^{10}=3.3^{10}.\left(2^3\right)^{10}=3^{11}.2^{30}< 3^{15}.2^{30}\)

\(\Rightarrow4^{30}=4^{15}.2^{30}>3^{15}.2^{30}>3^{11}.2^{30}=3.24^{10}\)

b/

\(=\dfrac{2^2-1^2}{1^2.2^2}+\dfrac{3^2-2^2}{2^2.3^2}+\dfrac{4^2-3^2}{3^2.4^2}+...+\dfrac{10^2-9^2}{9^2.10^2}=\)

\(=1-\dfrac{1}{2^2}+\dfrac{1}{2^2}-\dfrac{1}{3^2}+\dfrac{1}{3^2}-\dfrac{1}{4^2}+...+\dfrac{1}{9^2}-\dfrac{1}{10^2}=\)

\(=1-\dfrac{1}{10^2}< 1\)

a) 4³⁰ = (2²)³⁰ = 2⁶⁰ = 2³⁰.2³⁰ = 1073741824.2³⁰

3.24¹⁰ = 3.(3.2³)¹⁰ = 3.3¹⁰.2³⁰ = 3¹¹.2³⁰ = 177147.2³⁰

Do 1073741824 > 177147

⇒ 1073741824.2³⁰ > 177147.2³⁰

Vậy 4³⁰ > 3.24¹⁰

b) 3/(1².2²) + 5/(2².3²) + ... + 19/(9².10²)

= 1/1² - 1/2² + 1/2² - 1/3² + ... + 1/9² - 1/10²

= 1 - 1/100

= 99/100

Mà 99/100 < 1

⇒ 3/(1².2²) + 5/(2².3²) + 7/(3².4²) + ... + 19/(9².10²) < 1