b1,tính
a,\(\sqrt{\left(\sqrt{7}-4\right)^2}+\sqrt{8-2\sqrt{7}}\)
b,\(\sqrt{\left(\sqrt{5}-2\right)^2}+\sqrt{6+2\sqrt{5}}\)
b2,rút gọn các biểu thức sau
a,\(5\sqrt{\dfrac{1}{5}}+\dfrac{1}{2}\sqrt{20}+\sqrt{5}\)
b,\(\sqrt{\dfrac{1}{2}}+\sqrt{4,5}+\sqrt{12,5}\)
c,\(\sqrt{20}-\sqrt{45}+3\sqrt{18}+\sqrt{72}\)
d,\(0,1\times\sqrt{200}+2\times\sqrt{0,08}+0,4\times\sqrt{50}\)