Question

Rút gọn rồi tính

a)5\(\sqrt{\left(-2\right)^4}\)

b)-4\(\sqrt{\left(-3\right)^6}\)

c)\(\sqrt{\sqrt{\left(-5\right)^8}}\)

d)2\(\sqrt{\left(-5\right)^6}\) + 3\(\sqrt{\left(-2\right)^8}\)

Answer 1

a) \(5\sqrt{\left(-2\right)^4}=5\sqrt{\left(2^2\right)^2}=5\left|4\right|=5.4=20\)

Answer 2

b)\(-4\sqrt{\left(-3\right)^6}=-4\sqrt{\left(3^3\right)^2}=-4\left|27\right|=-4.27=-108\)

c) \(\sqrt{\sqrt{\left(-5\right)^8}}=\sqrt{\sqrt{\left(5^4\right)^2}}=\sqrt{\left(5^2\right)^2}=25\)

d)

Answer 3

\(2\sqrt{\left(-5\right)^6}+3\sqrt{\left(-2\right)^8}=2\sqrt{\left(5^3\right)^2}+3\sqrt{\left(2^4\right)^2}\)

\(=2.5^3+3.2^4=298\)