nhanh giúp tôi

de thui 

nhung bây giờ mk bận 

nên ko giải hộ bn được

chúc bn hoc tốt!

hihi

a, 3^x+3^x*3⁴ = 738

<=> 3^x(1+3⁴) =738

<=> 3^x *82 = 738

<=> 3^x         =9 =3²

<=> x=2

câu b,c tương tự

c) x . (x²)³ = x⁵

c) x . x⁶ = x⁵

x¹⁺⁶=x⁵

x⁷=x⁵

=>x=0;1

a) 2^x . 7 = 22⁴

 2^x . 7 = 234256

 2^x =234256:7

 2^x =đề sai

b) ( 3x + 5 )² = 289

( 3x + 5 )² = 17²

=>3x + 5=17

3x=17-5

3x=12

x=12:3

x=4

d) 3^{2x +1} .11 = 267³

 3^{2x +1} .11 = 19034163

 3^{2x +1} =19034163:11

 3^{2x +1} =đề sai

a) ( 3x + 5)² = 289

    289 : ( 3x + 5)^{2 =} ( 3x + 5)²

     Đổi: 289 = 17²      

     \(\Rightarrow\)3x + 5 = 17

             3 . x = 17 - 5

             3 . x = 12

                  x = 12 : 3

                  x = 4.

b) ( 2x + 1)³  = 125²

    ( 2x + 1)³  = 125 . 125

    ( 2x + 1)³  = 15625

Đổi: 15625 = 25³

\(\Rightarrow\)2x + 1 = 25

         2 . x = 25 - 1

         2 . x = 24

              x = 24 : 2

              x = 12.

c) ( 7x - 11 )³ = 2⁵ . 5² + 200

    ( 7x - 11 )³ = 2248

Đổi: 1000 = 10³

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

         7 . x = 10 + 11

         7 . x = 21

              x = 21 : 7

              x = 3

d) ( 2x - 2 )² = 64³

    ( 2x - 2 )² = 262144

Đổi: 262144 = 512²

\(\Rightarrow\) 2x - 2 = 512

         2 . x = 512 + 2

         2 . x = 514

              x = 514 : 2

              x = 257

K cho nha , ghi hoài mỏi tay quá!

Cấm Coppy dưới mọi hình thức! Trừ người này : phan thi phuong

a) \(\left(x-1\right)^3=125\)

\(\Leftrightarrow\left(x-1\right)^3=5^3\)

\(\Leftrightarrow x-1=5\)

\(\Leftrightarrow x=5+1\)

\(\Leftrightarrow x=6\)

Vậy \(x=6\)

b) \(2^{x+2}-2^x=96\)

\(\Leftrightarrow\left(2^2-1\right)\cdot2^x=96\)

\(\Leftrightarrow\left(4-1\right)\cdot2^x=96\)

\(\Leftrightarrow3\cdot2^x=96\)

\(\Leftrightarrow2^x=32\)

\(\Leftrightarrow2^x=2^5\)

\(\Leftrightarrow x=5\)

Vậy \(x=5\)

c) \(\left(2x+1\right)^3=343\)

\(\Leftrightarrow\left(2x+1\right)^3=7^3\)

\(\Leftrightarrow2x+1=7\)

\(\Leftrightarrow2x=7-1\)

\(\Leftrightarrow2x=6\)

\(\Leftrightarrow x=3\)

Vậy \(x=3\)

d) \(720:\left[41-\left(2x-5\right)\right]=2^3\cdot5\)

\(\Leftrightarrow720:\left[41-\left(2x-5\right)\right]=2^3\cdot5\left(đk:x\ne23\right)\)

\(\Leftrightarrow720:\left(41-2x+5\right)=8\cdot5\)

\(\Leftrightarrow720:\left(46-2x\right)=40\)

\(\Leftrightarrow\dfrac{720}{46-2x}=40\)

\(\Leftrightarrow\dfrac{720}{2\left(23-x\right)}=40\)

\(\Leftrightarrow\dfrac{360}{23-x}=40\)

\(\Leftrightarrow360=40\left(23-x\right)\)

\(\Leftrightarrow9=23-x\)

\(\Leftrightarrow x=23-9\)

\(\Leftrightarrow x=14\left(đk:x\ne23\right)\)

\(\Leftrightarrow x=14\)

Vậy \(x=14\)

e) \(2^x\cdot7=224\)

\(\Leftrightarrow7\cdot2^x=224\)

\(\Leftrightarrow2^x=32\)

\(\Leftrightarrow2^x=2^5\)

\(\Leftrightarrow x=5\)

Vậy \(x=5\)

f) \(\left(3x+5\right)^2=289\)

\(\Leftrightarrow3x+5=\pm17\)

\(\Leftrightarrow\left[{}\begin{matrix}3x+5=17\\3x+5=-17\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=4\\x=-\dfrac{22}{3}\end{matrix}\right.\)

Vậy \(x_1=-\dfrac{22}{3};x_2=4\)

a)\(\left(x-1\right)^3=125\Leftrightarrow\left(x-1\right)^3=5^3\Leftrightarrow x-1=5\Leftrightarrow x=6\)b)\(2^{x+2}-2^x=96\Leftrightarrow2^x.2^2-2^x=96\Leftrightarrow2^x\left(2^2-1\right)=96\Leftrightarrow2^x.3=96\Leftrightarrow2^x=32\Leftrightarrow x=5\)c)\(\left(2x-1\right)^3=343\Leftrightarrow\left(2x-1\right)^3=7^3\Leftrightarrow2x-1=7\Rightarrow2x=8\Rightarrow x=4\)d)\(720:\left[41-\left(2x-5\right)\right]=2^3.5\)

\(720:\left[41-\left(2x-5\right)\right]=40\Leftrightarrow\left[41-\left(2x-5\right)\right]=720:40=18\)

\(\Leftrightarrow41-2x+5=18\Leftrightarrow36-2x=18\Leftrightarrow2x=18\Leftrightarrow x=9\)

e)\(2^x.7=224\Leftrightarrow2^x=224:7=32\Leftrightarrow2^x=2^5\Leftrightarrow x=5\)

f) \(\left(3x+5\right)^2=289\Leftrightarrow\left(3x+5\right)=17^2\Leftrightarrow3x+5=17\Leftrightarrow3x=12\Leftrightarrow x=4\)