Question

tìm x 

11, (x+3)³ = 125

12, (2x)⁴ = 16

13, 32 : (3x - 2) = 2³

14, 20 - 2(x + 4) = 23

15, 14 ⋮(2.x+3)

16, 30- [4(x - 2)+15] = 3

17, 27 : ( x - 1)= 3²

18, (10 + 2x) : 4²⁰¹¹= 4²⁰¹³

19, (x + 5) ⋮(x +2)

20,[(8x - 12) : 4].3³=3⁶

mong các bạn giúp mình ^^

 

Answer 1

11: Ta có: \(\left(x+3\right)^3=125\)

\(\Leftrightarrow x+3=5\)

hay x=2

12: Ta có: \(\left(2x\right)^4=16\)

\(\Leftrightarrow x^4=1\)

hay \(x\in\left\{1;-1\right\}\)

Answer 2

11: Ta có: \left(x+3\right)^3=125(x+3)3=125

$\iff x+3=5$

hay x=2

12: Ta có: \left(2x\right)^4=16(2x)4=16

\Leftrightarrow x^4=1(2x)   = 2   =2  4

           4      

⇔2x=2⇔ x=1

13) 32:(3x-2)=2^3

32:(3x-2)=8

3x-2=32:8=4

3x=4+2=6

x=6:3=2

⇔x=2