Question

Tìm x \(\in\) Z biết:

a) x² = 16

b) x³ = -8

AI NHANH MK TICK.

Answer 1

a.

\(x^2=16\)

\(x^2=\left(\pm4\right)^2\)

\(x=\pm4\)

Vậy x = 4 hoặc x = -4

b.

x³ = -8

x³ = (-2)³

x = -2

Answer 2

\(a>x^2=16\)
\(x^2=4^2=\left(-4\right)^2\)
\(\Rightarrow x=\pm4\)
\(b>x^3=-8\)
\(x^3=\left(-2\right)^3\)
\(\Rightarrow x=-2\)

Answer 3

a) x=4 hoặc x= -4

b) x= -2