Question

Tính :

a /125^3 : 9^3

b/ 32^4 .4^3

Tìm x :

( x + 1/2 ) ^2 = 4/25

 

Answer 1

1.

a/ 125³ : 9³ = \(\left(\frac{125}{9}\right)^3\) = \(\frac{1953125}{729}\)

b/ 32⁴. 4³ = \(\left(2^5\right)^4.\left(2^2\right)^3\) = \(2^{20}.2^6\) = \(2^{26}\) =67108864

2. \(\left(x+\frac{1}{2}\right)^2=\frac{4}{25}\)

=> \(\left(x+\frac{1}{2}\right)^{ }=\frac{2^2}{5^2}\)

=>\(\left(x+\frac{1}{2}\right)^2=\left(\frac{2}{5}\right)^2\)

=> \(x+\frac{1}{2}=\frac{2}{5}\)

=> \(x=\frac{2}{5}-\frac{1}{2}=\frac{-1}{10}\)

Vậy \(x=\frac{-1}{10}\)