(7x-11)³=2⁵.5²+200

(7x-11)³=32.25+200

(7x-11)³=800+200

(7x-11)³=1000

(7x-11)³=10³

=> 7x-11=10

7x=10+11

7x=21

x=21/7

x=3

cảm ơn bạn nha

làm như nào nhỉ

\(\left(7x-11\right)^3=2^5.5^2+200\)

\(\Leftrightarrow\left(7x-11\right)^3=1000\)

\(\Leftrightarrow7x-11=10\)

\(\Leftrightarrow7x=21\)

\(\Leftrightarrow x=3\)

\(\left(7x-11\right)^3=2^5.5^2+200\)

\(\Rightarrow\left(7x-11\right)^3=32.25+200\)

\(\Rightarrow\left(7x-11\right)^3=800+200\)

\(\Rightarrow\left(7x-11\right)^3=1000=10^3\)

\(\Rightarrow7x-11=10\)

\(\Rightarrow7x=21\)

\(\Rightarrow x=3\)

\(\left(7x-11\right)^3=2^5.5^2+200\)

\(\Rightarrow\left(7x-11\right)^3=32.25+200\)

\(\Rightarrow\left(7x-11\right)^3=800+200\)

\(\Rightarrow\left(7x-11\right)^3=1000=10^3\)

\(\Rightarrow7x-11=10\)

\(\Rightarrow7x=21\)

\(\Rightarrow x=3\)

a) \(2^x\)\(-\)\(64\)\(=\)\(2^6\)

    \(2^x\)\(-\)\(2^6\)\(=\)\(2^6\)

           \(2^x\)          \(=\)\(2^6\)\(+\)\(2^6\)

           \(2^x\)          \(=\) \(64\)\(+\)\(64\)

            \(2^x\)         \(=\)        \(128\)

  \(\Rightarrow\) \(2^x\)          \(=\)         \(2^7\)

b) \(\left(7x-11\right)\)\(^3\)\(=\)\(2^5\)\(.\)\(5^2\)\(+\)\(200\)

    \(\left(7x-11\right)\)\(^3\)\(=\)\(32\)\(.\)\(25\)\(+\)\(200\)

    \(\left(7x-11\right)\)\(^3\)\(=\)           \(1000\)

    \(\left(7x-11\right)\)\(^3\)\(=\)            \(10^3\)

\(\Rightarrow\)\(7x-11\)\(=\)\(10\)

               \(7x\)       \(=\)\(10+11\)

               \(7x\)        \(=\)    \(21\)

                  \(x\)        \(=\) \(21\)\(:\)\(7\)

                 \(x\)         \(=\)      \(3\)

\(2^x-64=2^6\)

\(2^x-64=64\)

\(2^x=64+64\)

\(2^x=128\)

\(\)Vì \(128=2^7\) \(\Rightarrow x=7\)

a, 2^x-64=2⁶

=> 2^x-64=64

=> 2^x=64-64

=> 2^x=0

=> x=0

b, (7x-11)³=2⁵.5²+200

=> (7x-11)³=32.25+200

=> (7x-11)³=1000

=> (7x-11)³=10³

=> 7x-11=10

=> 7x=10+11

=> 7x=21

=> x=21:7

=> x=3

\(\left(x-2\right)^8=\left(x-2\right)^6\)

\(\Leftrightarrow\left(x-2\right)^8-\left(x-2\right)^6=0\)

\(\Leftrightarrow\left(x-2\right)^6\left[\left(x-2\right)^2-1\right]=0\)

\(\Leftrightarrow\left(x-2\right)^6\left(x-3\right)\left(x-1\right)=0\)

\(\Rightarrow x=2;x=3;x=1\)

=>x-2=0 hoặc x-2=1

=>x-2=0=>x=2

=>x-2=1=>x=3

\(\left(x-2\right)^8=\left(x-2\right)^6\)

\(\left(x-2\right)^8-\left(x-2\right)^6=0\)

\(\left(x-2\right)^6.\left[\left(x-2\right)^2-1\right]=0\)

\(\Rightarrow\orbr{\begin{cases}\left(x-2\right)^6=0\\\left(x-2\right)^2-1=0\end{cases}\Rightarrow\orbr{\begin{cases}x-2=0\\\left(x-2\right)^2=1\end{cases}\Rightarrow}\orbr{\begin{cases}x=2\\x-2=1\end{cases}\Rightarrow}\orbr{\begin{cases}x=2\\x=3\end{cases}}}\)

(7x-11)³ = 2⁵.5²+ 2³.5²

(7x-11)³ = 2³.5²( 2²+1)

(7x-11)³ = 2³.5³=(2.5)³ 

7x-11=10

x=3

ban anhduc1501 hinh nhu lam chua dung to nghi vay

(7x - 11)³ = 2⁵ . 5² + 200

(7x - 11)³ = 32 . 25 + 200

(7x - 11)³ = 800 + 200

(7x - 11)³ = 1000

(7x - 11)³ = 10³

7x - 11 = 10

7x = 21

x = 3

\(=\left(\dfrac{88}{132}-\dfrac{33}{132}+\dfrac{60}{132}\right):\left(\dfrac{55}{132}-\dfrac{132}{132}-\dfrac{84}{132}\right)\)

\(=\dfrac{115}{-161}=-\dfrac{115}{161}\)

         1^3+2^3+3^3+...+10^3=(x-1)^2

<=>(1+2+3+...+10)^2=(x-1)^2

<=>55^2=(x-1)^

<=>55=x-1

<=>x=54

\(\Rightarrow\left(7n-11\right)^3=32\times25+200\)

\(\Rightarrow\left(7n-11\right)^3=1000\)

\(\Rightarrow7n-11=10\)

\(\Rightarrow7n=10+11\)

\(\Rightarrow n=21:7=3\)

\(\left(7n-11\right)^3=2^5.5^2+200\)

\(\left(7n-11\right)^3=32.25+200\)

\(\left(7n-11\right)^3=800+200\)

\(\left(7n-11\right)^3=1000\)

=>TH1:(7n-11)³=10³

=>7n-11=10

=>7n=10+11=21

=>n=21:7=3

TH2: (7n-11)³=-10³

=>7n-11=-10

=>7n=-10+11

=>7n=1

=>n=1:7=1/7

Mà n thuộc N nên n=3

Kết luận n=3

Trà My~ Cần j lm 2 TH; you lm sai roay đs. Vì nếu (7n-11)³=-10 thì lm sao -10³=1000 cho được

Đề bằng 1 thì (x-2)(x+3)=0 suy ra x=2 hoặc x=-3.

thanks bạn

\(5^{\left(x-2\right)\left(x+3\right)}=1\)

đặt tổng của (x-2)(x+3) là a

\(\Leftrightarrow5^a=1\)

\(\Leftrightarrow x=0\)

thay vào \(\left(x-2\right)\left(x+3\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}x-2=0\\x+3=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=2\\x=-3\end{cases}}}\)

vậy x=2 hoặc x=-3