Question

Tính:

a) \(\sqrt{\left(-10\right)^2}\);             b) \(\sqrt{\left(-\dfrac{2}{7}\right)^2}\);               c) \(\left(-\sqrt{2}\right)^2-\sqrt{25}\);               d) \(\left(-\sqrt{\dfrac{2}{3}}\right)^2.\sqrt{0,09}\).

Answer 1

a) \(\sqrt {{{\left( { - 10} \right)}^2}}  = \left| { - 10} \right| = 10\)

b) \(\sqrt {{{\left( { - \frac{2}{7}} \right)}^2}}  = \left| { - \frac{2}{7}} \right| = \frac{2}{7}\)

c) \({\left( { - \sqrt 2 } \right)^2} - \sqrt {25}  = 2 - 5 =  - 3\)

d) \({\left( { - \sqrt {\frac{2}{3}} } \right)^2}.\sqrt {0,09}  = \frac{2}{3}.0,3 = 0,2\)