Question

Tính:

a) \(\sqrt{a^2}\) với a= 6,5 ; -0,1   b)\(\sqrt{a^4}\) với a= 3; -0,1    c)\(\sqrt{a^6}\) với a= -2; 0,1

Answer 1

a) \(\sqrt{a^2}=\left|a\right|\)

Khi \(a=6,5\Rightarrow\sqrt{a^2}=\left|6,5\right|=6,5\)

Khi \(a=-0,1\Rightarrow\sqrt{a^2}=\left|-0,1\right|=0,1\)

b) \(\sqrt{a^4}=\left|a^2\right|=a^2\)

Khi \(a=3\Rightarrow\sqrt{a^4}=3^2=9\)

Khi \(a=-0,1\Rightarrow\sqrt{a^4}=\left(-0,1\right)^2=0,01\)

c) \(\sqrt{a^6}=\left|a^3\right|\)

Khi \(a=-2\Rightarrow\sqrt{a^6}=\left|\left(-2\right)^3\right|=\left|-8\right|=8\)

Khi \(a=0,1\Rightarrow\sqrt{a^6}=\left|0,1^3\right|=0,001\)