Question

Tính

A) a²/bc³√b²(a-b) ²/a⁴ (b>0; a≠0;a<b)

B) √3+2√2

C) √11-6√2

Answer 1

a) \(\frac{a^2}{bc^3}\cdot\sqrt{\frac{b^2\left(a-b\right)^2}{a^4}}=\frac{a^2}{bc^3}\cdot\frac{b\left(b-a\right)}{a^2}=\frac{b-a}{c^3}\)

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

c) \(\sqrt{11-6\sqrt{2}}=\sqrt{3^2-2\cdot3\cdot\sqrt{2}+2}=\sqrt{\left(3-\sqrt{2}\right)^2}=3-\sqrt{2}\)