\(\text{Rút gọn các căn thức sau:}\)\(\sqrt{\frac{4}{\left(2-\sqrt{5}\right)^2}}-\sqrt{\frac{4}{\left(2+\sqrt{5}\right)^2}}\)\(\left(2\sqrt{8}+3\sqrt{5}-7\sqrt{2}\right)\left(\sqrt{72}-5\sqrt{20}-2\sqrt{2}\right)\)\(\sqrt{\frac{2-\sqrt{3}}{2}}+\frac{1-\sqrt{3}}{2}\)\(\sqrt{3+2\sqrt{2}}+\sqrt{6-4\sqrt{4}}\)K lm tắt nhé...
Đọc tiếp
\(\text{Rút gọn các căn thức sau:}\)
\(\sqrt{\frac{4}{\left(2-\sqrt{5}\right)^2}}-\sqrt{\frac{4}{\left(2+\sqrt{5}\right)^2}}\)
\(\left(2\sqrt{8}+3\sqrt{5}-7\sqrt{2}\right)\left(\sqrt{72}-5\sqrt{20}-2\sqrt{2}\right)\)
\(\sqrt{\frac{2-\sqrt{3}}{2}}+\frac{1-\sqrt{3}}{2}\)
\(\sqrt{3+2\sqrt{2}}+\sqrt{6-4\sqrt{4}}\)
K lm tắt nhé !
mik làm bài này
linh tinh
bn ơi
cho mik
xin 1 L-I-K-E
b,
+x^3(x+1)+2x^2(x+1)+x(x+1)+(x+1)=0)
(x^4+x^3+2x^2+x+1)=0)
+13x^2(x+2)-14x(x+2)+3(x+2)=0)
(6x^3+13x^2-14x+3)=0)
(6x^3+18x^2-5x^2-15x+x+3)=0)
[6x^2(x+3)-5x(x+3)+(x+3)]=0)
(x+3)(6x^2-5x+1)=0)
(x+3)(6x^2-3x-2x+1)=0)
(x+3)[6x(x-\frac{1}{2})-2(x-\frac{1}{2})]=0)
(x+3)(x-\frac{1}{2})(6x-2)=0)
d,
\(\sqrt{\frac{4}{\left(2-\sqrt{5}\right)^2}}-\sqrt{\frac{4}{\left(2+\sqrt{5}\right)^2}}\)
\(=\frac{2}{\sqrt{5}-2}-\frac{2}{2+\sqrt{5}}\)
\(=\frac{2\left(\sqrt{5}+2\right)-2\left(\sqrt{5}-2\right)}{5-4}\)
\(=2\sqrt{5}+4-2\sqrt{5}+4\)
\(=8\)