\(\sqrt{\left(2-\sqrt{3}\right)^2}+\sqrt{\left(4-2\sqrt{3}\right)}=2-\sqrt{3}+\sqrt{3}-1=1\)
\(\sqrt{\left(2-\sqrt{3}\right)^2}+\sqrt{\left(4-2\sqrt{3}\right)}=2-\sqrt{3}+\sqrt{3}-1=1\)
Rút gọn:
\(2\left(\sqrt{10}-\sqrt{2}\right)\sqrt{4+\sqrt{6-2\sqrt{5}}}\)
\(\left(4\sqrt{2}+\sqrt{30}\right)\left(\sqrt{5}-\sqrt{3}\right)\sqrt{4-\sqrt{15}}\)
Rút gọn các biểu thức sau :
a) \(\left(\sqrt{8}-3\sqrt{2}+\sqrt{10}\right)\sqrt{2}-\sqrt{5}\)
b) \(0,2\sqrt{\left(-10\right)^2.3}+2\sqrt{\left(\sqrt{3}-\sqrt{5}\right)^2}\)
c) \(\left(\dfrac{1}{2}\sqrt{\dfrac{1}{2}}-\dfrac{3}{2}\sqrt{2}+\dfrac{4}{5}\sqrt{200}\right):\dfrac{1}{8}\)
d) \(2\sqrt{\left(\sqrt{2}-3\right)^2}+\sqrt{2.\left(-3\right)^2}-5\sqrt{\left(-1\right)^4}\)
Bài 1 :tính giá trị của biểu thức
a) \(\left(\sqrt{5}+\sqrt{2}\right)\left(3\sqrt{2}-1\right)\)
b) \(3\sqrt{50}-2\sqrt{75}-4\dfrac{\sqrt{54}}{\sqrt{3}}-3\sqrt{\dfrac{1}{3}}\)
c) \(\sqrt{\left(\sqrt{3}-3\right)^2}+\sqrt{4+2\sqrt{3}}\)
d) \(\sqrt{48-2\sqrt{135}}-\sqrt{45}+\sqrt{18}\)
e)\(\dfrac{5\sqrt{2}-2\sqrt{5}}{\sqrt{5}-\sqrt{2}}+\dfrac{6}{2-\sqrt{10}}-\dfrac{20}{\sqrt{10}}\)
Bài 2 :Tính:
a) \(3\sqrt{2x}-5\sqrt{8x}+7\sqrt{18x}\)
b) \(\left(2\sqrt{3}+4\right)\left(\sqrt{3}-2\right)\)
c) \(\sqrt{3+2\sqrt{2}}+\sqrt{\left(\sqrt{2}-2\right)^2}\)
d)\(\sqrt{4-\sqrt{15}}-\sqrt{4+\sqrt{15}}+\sqrt{6}\)
e)\(\left(\dfrac{5-\sqrt{5}}{\sqrt{5}}-2\right)\left(\dfrac{4}{1+\sqrt{5}}+4\right)\)
f) \(\dfrac{1}{5}\sqrt{50}-2\sqrt{96}-\dfrac{\sqrt{30}}{\sqrt{15}}+12\sqrt{\dfrac{1}{6}}\)
tính
a, \(\sqrt{\left(3-\sqrt{5}\right)^2}\) - \(\sqrt{5}\)
b \(\sqrt{\left(4-2\sqrt{3}\right)^2}\)
Dạng 3.Chứng minh đẳng thức
Bài 1: CM
a)\(\left(4+\sqrt{15}\right)\left(\sqrt{10}-\sqrt{6}\right)\sqrt{4-\sqrt{15}}=2\)
b)\(\left(5+\sqrt{21}\right)\left(\sqrt{14}-\sqrt{6}\right)\sqrt{5-\sqrt{21}}=8\)
Bài 2 :CM
\(\dfrac{\sqrt{\sqrt{5}+2}+\sqrt{\sqrt{5}-2}}{\sqrt{2}}=\sqrt{\sqrt{5}+1}\)
Giair phương trình:
1) \(\sqrt[5]{32-x^2}-\sqrt[5]{1-x^2}=4\)
2) \(\sqrt{x}+\sqrt[4]{20-x}=4\)
3) \(x^3+1=2\sqrt{3x-1}\)
4) \(\sqrt[3]{x-1}+3=\sqrt[4]{82-x}\)
5)
\(a.\left(x+3\sqrt{x}+2\right)\left(x+9\sqrt{x}+18\right)=168x\)
\(b.\sqrt{5x^2+14x+9}-\sqrt{x^2-x-20}=5\sqrt{x+1}\)
\(\left(\dfrac{3}{2}\sqrt{6\:\:}+\:2\sqrt{\dfrac{2}{3}\:\:\:\:\:\:\:\:\:}-4\sqrt{\dfrac{3}{2}}\right)\left(3\sqrt{\dfrac{2}{3}}-\sqrt{12}-\sqrt{6}\right)\)
Rút gọn
a) \(\left(\dfrac{\sqrt{5}-2}{\sqrt{5}+2}+1\right).\dfrac{1}{2}+\sqrt{\left(2-4\sqrt{5}\right)^2}\)
b) \(\left(4\sqrt{2}+\sqrt{30}\right).\left(\sqrt{5}-\sqrt{3}\right).\sqrt{4-\sqrt{15}}\)
1,Rút gọn
a, \(\left(2\sqrt{2}-1\right)\left(\sqrt{8}+1\right)\)
b, \(\left(\sqrt{12}+\sqrt{75}-2\sqrt{27}\right):\sqrt{3}\)
c, \(\sqrt{3+2\sqrt{2}}+\sqrt{6-4\sqrt{2}}\)
d, \(\sqrt{6+2\sqrt{5}}+\sqrt{6-2\sqrt{5}}\)
e, \(\left(\sqrt{3}-\sqrt{2}\right)\sqrt{5+2\sqrt{6}}\)
f, \(\sqrt{8-2\sqrt{15}}-\sqrt{23-4\sqrt{15}}\)
1 Rút gọn:
a) A=\(\frac{\sqrt[]{2+\sqrt[]{3}}}{4}+\sqrt[]{\frac{2-\sqrt[]{3}}{16}}+\frac{1}{\sqrt[]{3}+\sqrt[]{2}+1}\)
b)\(\left(\sqrt[]{a+\sqrt[]{a^2-8}}\right).\left(\sqrt[]{a-2\sqrt[]{2}}-\sqrt[]{a+2\sqrt[]{2}}\right),a>=2\sqrt[]{2}\)
2.Cho x= \(\sqrt[]{2-\sqrt[]{3}}.\left(\sqrt[]{6}+\sqrt[]{2}\right)-\frac{2\sqrt[]{6}+\sqrt[]{3}}{\sqrt[]{8}+1}\). Tính A= \(x^5-3x^4-3x^3+6x^2-20x+2022\)
3. Cho a,b,c >0, \(\frac{a}{a+b}=\frac{b}{c+a}=\frac{c}{a+b}\). CMR: \(\frac{\left(a+b\right)^3}{c^3}+\frac{\left(b+c\right)^3}{a^3}+\frac{\left(a+c\right)^3}{b^3}+24\)