\(B=\left|x-33\right|+\left|x+34\right|+\left|x+35\right|\)

\(B=\left(\left|x-33\right|+\left|x+34\right|\right)+\left|x+35\right|\)

\(B=\left(\left|33-x\right|+\left|x+34\right|\right)+\left|x+35\right|\ge\left|33-x+x+34\right|+\left|x+35\right|=67+\left|x+35\right|\ge67\)

Dấu '' = '' xảy ra 

\(\Leftrightarrow\hept{\begin{cases}\left(33-x\right)\left(x+34\right)\ge0\\x+35=0\end{cases}}\Leftrightarrow\hept{\begin{cases}-34\le x\le33\\x=-35\end{cases}}\)

Vậy ..............................

B nhỏ nhất suy ra |x-33|+|x+34|+|x+35| nhỏ nhất

suy ra |x-33|+|x+34|+|x+35|=0

suy ra x-33+x+34+x+35=0

suy ra3x+36=0 suy ra 3x=-36

suy ra x=-12 ..................................................................................................................................................................................................

Kimetsu no Yaiba, Dấu bằng không đồng thời xảy ra nên bài của bạn sai nhé

A) 34*34 PHẦN 33*35=1156/1155. VẬY PHÂN SỐ ĐÓ LỚN HƠN 1

B)1991*1999 PHẦN 1995*1995=3980009/3980025. VẬY PHÂN SỐ ĐÓ BÉ HƠN 1

a)34*34/33*35>1

b)1991*1999/1995*1995>1

câu a bằng \(\frac{1156}{1155}\)

câu b bằng \(\frac{3980009}{3980025}\)

1) 42/35 - [ 33/14 . 21/22 - ( 54/25 : 27/25 - 7/10 )]

= 42/35 - ( 9/4-13/10)

=42/35-19/20

=1/4

2) a) 5/21 . x/34 = 35/102     

x/34=35/102 : 5/21

x/34=49/34

=> x=34

Vậy x=34

b) 15/x . 21/13 = 45/91

15/x=45/91 : 21/13

15/x=15/49

=> x=49

Vậy x=49

lớp 4

A=34^33.(34-1)=33.34^33

​

​b=34^35.(34-1)=33.34^35

​b>a

​

Mình thấ bài này hơi khó sao chúng ta ko thử giải theo cách khác

34^34-34³³>34³⁵ -34³⁴

\(\frac{x+32}{11}+\frac{x+33}{12}=\frac{x+34}{13}+\frac{x+35}{14}\)

\(\Leftrightarrow\left(\frac{x+32}{11}-1\right)+\left(\frac{x+33}{12}-1\right)=\left(\frac{x+34}{13}-1\right)+\left(\frac{x+35}{14}-1\right)\)

\(\Leftrightarrow\frac{x-21}{11}+\frac{x-21}{12}=\frac{x-21}{13}+\frac{x-21}{14}\)

\(\Leftrightarrow\left(x-21\right)\left(\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\right)=0\)

Vì \(\left(\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\right)\ne0\)

\(\Rightarrow x-21=0\Rightarrow x=21\)

\(\frac{x+32}{11}+\frac{x+33}{12}=\frac{x+34}{13}+\frac{x+35}{14}\)

\(\Leftrightarrow\left(\frac{x+32}{11}-1\right)+\left(\frac{x+33}{12}-1\right)=\left(\frac{x+34}{13}-1\right)+\left(\frac{x+35}{14}-1\right)\)( trừ cả hai vế cho 2 )

\(\Leftrightarrow\frac{x-21}{11}+\frac{x-21}{12}=\frac{x-21}{13}+\frac{x-21}{14}\)

\(\Leftrightarrow\frac{x-21}{11}+\frac{x-21}{12}-\frac{x-21}{13}-\frac{x-21}{14}=0\)

\(\Leftrightarrow\left(x-21\right)\left(\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\right)=0\)

Mà  \(\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\ne0\)

\(\Rightarrow x-21=0\)

\(\Leftrightarrow x=21\)

Vậy  \(x=21\)

\(\dfrac{x+32}{11}+\dfrac{x+33}{12}=\dfrac{x+34}{13}+\dfrac{x+35}{14}\)

\(\Leftrightarrow\left(\dfrac{x+32}{11}-1\right)+\left(\dfrac{x+33}{12}-1\right)=\left(\dfrac{x+34}{13}-1\right)+\left(\dfrac{x+35}{14}-1\right)\)

\(\Leftrightarrow\dfrac{x+21}{11}+\dfrac{x+21}{12}=\dfrac{x+21}{13}+\dfrac{x+21}{14}\)

\(\Leftrightarrow\dfrac{x+21}{11}+\dfrac{x+21}{12}-\dfrac{x+21}{13}-\dfrac{x+21}{14}=0\)

\(\Leftrightarrow\left(x+21\right)\left(\dfrac{1}{11}+\dfrac{1}{12}-\dfrac{1}{13}-\dfrac{1}{14}\right)=0\)

Mà \(\dfrac{1}{11}+\dfrac{1}{12}-\dfrac{1}{13}-\dfrac{1}{14}\ne0\)

\(\Leftrightarrow x+21=0\)

\(\Leftrightarrow x=-21\)

Vậy ..