( -4/3 x 7/8 + 5/8 x 4/3 ) : ( -3)

= ( -7/6 + 5/6 ) : ( -3)

= -1/3 : -3

= 1/9

( -4/3 x 7/8 + 5/8 x 4/3 ) : ( -3)

= ( -7/6 + 5/6 ) : ( -3)

= -1/3 : -3

= 1/9

\(\frac{\sqrt{2^3\cdot3^4\cdot5^5\cdot6^6\cdot7^7}}{2^2\cdot3^2\cdot5^6\cdot6^3\cdot7^3}=\frac{2\cdot3^2\cdot5^2\cdot6^3\cdot7^3\cdot\sqrt{2\cdot5\cdot7}}{2^2\cdot3^2\cdot5^6\cdot6^3\cdot7^3}=\frac{\sqrt{2\cdot5\cdot7}}{2\cdot5^4}=\frac{\sqrt{70}}{1250}\)

a)\(A=\left|3,7-x\right|+2,5\)

Có\(\left|3,7-x\right|\ge0\)

\(\Rightarrow A\ge0+2,5=2,5\)

Dấu "=" xảy ra khi \( \left|3,7-x\right|=0\Rightarrow x=3,7\)

Vậy Min A = 2,5 <=> x = 3,7

b)\(B=\left|x+1,5\right|-4,5\)

Có \(\left|x+1,5\right|\ge0\)

\(\Rightarrow B\ge-4,5\)

Dấu "=" xảy ra khi x + 1,5 = 0 <=> x = -1,5

Vậy Min B = -4,5 <=> x = -1,5

A=2,5; KHI GTTT của 3.7-x =0

B=-4,5; khi GTTT của x+1,5=0

ĐÂY LÀ MK LÀM THEO BÀI CÓ ĐỀ LÀ: Tìm giá trị nhỏ nhất của nó

còn nếu bn muốn biết rõ cách làm thì bn phải viết đề ra nhé!

KẾT BẠN VS MK NHÉ!(^-^) 

\(A=\left|3,7-x\right|+2,5\ge2,5\)

\(MinA=2,5\Leftrightarrow3,7-x=0\Rightarrow x=3,7\)

\(B=\left|x+1,5\right|+4,5\ge4,5\)

\(MinB=4,5\Leftrightarrow x+1,5=0\Rightarrow x=-1,5\)

Ta có:

\(\frac{2^3.3^4}{2^2.3^2.5}=\frac{2.3^2}{5}=\frac{18}{5}\)

\(\frac{2^4.5^2.11^2.7}{2^3.5^3.7^2.11}=\frac{2.11}{5.7}=\frac{22}{35}\)

\(E=\frac{\frac{4}{3\cdot7}-\frac{4}{11.15}}{1-\frac{3}{7}-\frac{3}{11}+\frac{1}{5}}-\left(\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{2006.2007}\right)\)

\(=\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{11}+\frac{1}{15}}{\frac{192}{385}}-\left(\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-...+\frac{1}{2006}-\frac{1}{2007}\right)\)

\(=\frac{\frac{64}{385}}{\frac{192}{385}}-\left(\frac{1}{3}-\frac{1}{2007}\right)\)

\(=\frac{1}{3}-\left(\frac{1}{3}-\frac{1}{2007}\right)=\frac{1}{2007}\)

Vậy : \(E=\frac{1}{2007}\)

bạn viết mik ko hiểu cái j hết

ko

jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj123343345466

A.\(\frac{2^3.9^2}{2^2.3^2.5}=\frac{2^2.2.\left(3^2\right)^2}{2^2.3^2.5}=\frac{2.3^2}{5}=\frac{18}{5}\)

B.\(\frac{2^4.5^5.11^2.7}{2^3.5^3.7^2.11}=\frac{2^3.2.5^3.5^2.11.11.7}{2^3.5^3.7.7.11}=\frac{2.5^2.11}{7}=\frac{61}{7}\)

gfsfgd';;;;;;;;;;;;;;;;;;;;;

ngu 

tao lop5 ok

1. Tìm x, biết:

a) \(\frac{4}{x}=\frac{8}{6}\). Ta có: \(\frac{8}{6}=\frac{8:2}{6:2}=\frac{4}{3}\Rightarrow x=3\)

b) \(\frac{3}{x-5}=\frac{4}{x+2}\). Ta có: \(5-2=3\)

\(\Rightarrow x=\left(3.5\right)+\left(4.2\right)+3=15+8+3=26\)

c) \(\frac{x}{-2}=\frac{-8}{x}\Rightarrow x=\left(-8\right):\left(-2\right)=4\)

2. Rút gọn

a) \(\frac{2^4.5^2.11^2.7}{2^3.5^3.7^2.11}\Leftrightarrow\frac{2^3.2^1.5^2.11.11.7}{2^3.5^2.5^1.7.7.11}\Leftrightarrow\frac{2^1.11}{5^1.7}=\frac{22}{35}\)

b) Tương tự

c) Tương tự

\(\frac{4}{x}=\frac{8}{6}\Rightarrow x=\frac{4.6}{8}=3\)

\(\frac{3}{x-5}=\frac{-4}{x+2}\Rightarrow3\left(x+2\right)=-4\left(x-5\right)\)

                                \(\Rightarrow3x+6=-4x+20\)

                                \(\Rightarrow3x+4x=20-6\)

                                \(\Rightarrow7x=14\)

                                \(\Rightarrow x=2\)

\(\frac{x}{-2}=\frac{-8}{x}\Rightarrow x^2=\left(-8\right)\left(-2\right)=16\Rightarrow x=\pm4\)

\(\frac{4}{x}=\frac{8}{6}\)

\(\Rightarrow4\cdot6=x\cdot8\)

\(\Rightarrow x=\frac{4\cdot6}{8}\)

\(\Rightarrow x=3\)