Question

Tính a, √3^2 - √(-7)^2+√(-1)^2 b, -2√(-2)^2+3√(-5)^2+√3^2 c, √(2-√2)^2+√(2+√2)^2 d, √(3-√2)^2 - √(1-√2)^2 Giúp mình với ạaa

Answer 1

\(a,\sqrt{3^2}-\sqrt{\left(-7\right)^2}+\sqrt{\left(-1\right)^2}\)

\(=3-7+1\)

\(=-3\)

\(b,-2\sqrt{\left(-2\right)^2}+3\sqrt{\left(-5\right)^2}+\sqrt{3^2}\)

\(=-2.2+3.5+3\)

\(=-4+15+3\)

\(=14\)

\(c,\sqrt{\left(2-\sqrt{2}\right)^2}+\sqrt{\left(2+\sqrt{2}\right)^2}\)
\(=\left|2-\sqrt{2}\right|+\left|2+\sqrt{2}\right|\)

\(=2-\sqrt{2}+2+\sqrt{2}\)

\(=4\)

\(d,\sqrt{\left(3-\sqrt{2}\right)^2}-\sqrt{\left(1-\sqrt{2}\right)^2}\)

\(=\left|3-\sqrt{2}\right|-\left|1-\sqrt{2}\right|\)

\(=3-\sqrt{2}-\left(-1+\sqrt{2}\right)\)

\(=3-\sqrt{2}+1-\sqrt{2}\)

\(=-2\sqrt{2}+4\)