a, A(x)= (5.1)³ - (3.1)+4

           = 125-7

           =118

a) 

 tại\(x = 1 , GTBT A(x)\) là:

\(5.1 ^3 − 3.1 + 4\)

\(= 5.1 − 3.1 + 4\)

\(= 5 − 3 + 4\)

\(= 2 + 4\)

\(=6\)

Vậy tại\(x = 1 , GTBT A ( x ) là 6\)

B(y)= 4.5-7

      =13

Biểu thức trên tương đương với:

\(\frac{4^6}{3^6}.\frac{6^6}{2^6}=8^x\Leftrightarrow\frac{24^6}{6^6}=4^6=64^2=8^4\Leftrightarrow x=4\)

\(\frac{4^5+4^5+4^5+4^5}{3^5+3^5+3^5}.\frac{6^5+6^5+6^5+6^5+6^5}{2^5+2^5}=\frac{4^6}{3^6}.\frac{6^6}{2^6}=\frac{2^{12}.3^6.2^6}{3^6.2^6}=2^{12}\)

@PTAN@ 

tìm x mak sao ko tìm????

Giúp mình vs ạ. Cần gấp

\(\dfrac{3}{4}\)+\(\dfrac{1}{4}\): x=\(\dfrac{-2}{5}\)

⇒\(\dfrac{1}{4}\):x=\(\dfrac{-2}{5}\)-\(\dfrac{3}{4}\)

⇒ x=\(\dfrac{1}{4}\): \(\dfrac{-23}{20}\)

⇒ x=\(\dfrac{-5}{23}\)

3/15, 3/5, 6/5, 8/5

giúp mình với, đi mà mọi người

3/15; 3/5; 6/5; 8/5

20+24=44

10+3=13

k mk nhé

20+24=44

3+10=13

k mik nha

20+24=48

3+10=13

Kb vs mik nhé

X x 2+X x 1/6 =8/5

=> X x (2+1/6)=8/5

=> X x 13/6=8/5

 =>         X  =8/5:13/6

=>         X   =48/65

\(x\times2+x\times\dfrac{1}{6}=\dfrac{8}{5}\)

\(\Leftrightarrow2x\times2\times\dfrac{1}{6}=\dfrac{8}{5}\)

\(\Leftrightarrow2x\times\dfrac{1}{3}=\dfrac{8}{5}\)

\(\Leftrightarrow2x=\dfrac{8}{5}:\dfrac{1}{3}\)

\(\Leftrightarrow2x=\dfrac{8}{5}\times\dfrac{3}{1}\)

\(\Leftrightarrow2x=\dfrac{24}{5}\)

\(\Leftrightarrow x=\dfrac{24}{5}:2\)

\(\Leftrightarrow x=\dfrac{24}{5}\times\dfrac{1}{2}\)

\(\Leftrightarrow x=\dfrac{24}{10}\)

\(\Leftrightarrow x=\dfrac{12}{5}\)

sửa hộ chỗ nay thành này nha mình bấm nhanh quá nên hơi lỗi

c1:6/5

c2: thieu de bai

3/7 : 5/14 = 3/7 x 14/5 = 42/35

đề sai

\(\frac{2^{20}.9^3+15.4^9.81^2}{6^8.2^{11}+12^{10}}\)

\(=\frac{2^{20}.3^6+5.2^{18}.3^9}{2^{19}.3^8+2^{20}.3^{10}}\)

\(=\frac{2^{18}.3^6.\left(2^2+5.3^3\right)}{2^{19}.3^8.\left(1+2.3^2\right)}=\frac{139}{2.3^2.19}=\frac{139}{342}\)

CÔNG CHÚA ORI bạn có thể ghi bước trung gian đoạn cuối giúp mk đc ko??? Mk ko hỉu cho lắm

\(\frac{2^{20}.9^3+15.4^9.81^2}{6^8.2^{11}+12^{10}}\)

\(=\frac{2^{20}.3^6+3.5.2^{18}.3^8}{2^8.3^8.2^{11}+4^{10}.3^{10}}\)

\(=\frac{2^{20}.3^6+2^{18}.3^9.5}{2^{19}.3^8+2^{20}.3^{10}}\)

\(=\frac{2^{18}.3^6\left(2^2+3^3.5\right)}{2^{19}.3^8\left(1+2.3^2\right)}\)

\(=\frac{4+27.5}{2.3^2\left(1+18\right)}\)

\(=\frac{4+135}{18.19}\)

\(=\frac{139}{342}\)