Question

[Christina Nguyễn]

a)  x : (-1/2)^3 = -1/2

b) (x - 2)^2 = 1 

c) (2x -1 )^3 = 8

Answer 1

[Nguyễn Kiên]

a)  x : (-1/2)^3 = -1/2

=>x = (-1/2)^4 = 1/16

b) (x - 2)^2 = 1 

=> (x - 2)^2 = 1^2 = (-1)^2 (Do 1 = 1 ^2 = (-1)^2)

=> x - 2 = 1 hoặc x - 2 = -1

=> x = 3 hoặc x = 1

c) (2x -1 )^3 = 8

=>(2x-1)^3 = 2^3

=>2x-1 = 2

=>2x = 3

=>x=3/2

Answer 2

[công chúa xinh xắn]

\(a,x:\left(-\frac{1}{2}\right)^3=-\frac{1}{2}\)

                     \(x=\left(-\frac{1}{2}\right)\times\left(-\frac{1}{2}\right)^3\)

                     \(x=\left(-\frac{1}{2}\right)^4\)

                     \(x=\frac{1}{16}\)

\(b,\left(x-2\right)^2=1\)

\(\Rightarrow\left(x-2\right)^2=1^2\)

\(\Rightarrow x-2=1\)

\(\Rightarrow x=1+2\)

\(\Rightarrow x=3\)

\(c,\left(2x-1\right)^3=8\)

\(\Rightarrow\left(2x-1\right)^3=2^3\)

\(\Rightarrow2x-1=2\)

\(\Rightarrow2x=2+1\)

\(\Rightarrow2x=3\)

\(\Rightarrow x=\frac{3}{2}\)