1. So sánh
a) \(4+\sqrt{33}va\sqrt{29}+\sqrt{14}\)
b) \(\sqrt{23}+\sqrt{15}va\sqrt{91}\)
So sánh \(4+\sqrt{33}va\sqrt{29}+\sqrt{14}\)
\(4+\sqrt{33}=\sqrt{16}+\sqrt{33}\)
Có: \(\sqrt{16}>\sqrt{14}\)
\(\sqrt{33}>\sqrt{29}\)
=> \(\sqrt{16}+\sqrt{33}>\sqrt{29}+\sqrt{14}\)
=> \(4+\sqrt{33}>\sqrt{29}+\sqrt{14}\)
So sánh:
a) 4+\(\sqrt{33}\)và \(\sqrt{29}\)+\(\sqrt{14}\)
b) \(\sqrt{48}\)+ \(\sqrt{120}\)và 18
c) \(\sqrt{23}\)+ \(\sqrt{15}\)và \(\sqrt{91}\)
so sanh 4+\(\sqrt{33}va\sqrt{29}+\sqrt{14}\)
Ta có :
\(4+\sqrt{33}>4+\sqrt{25}=4+5=9\)
\(\sqrt{29}+\sqrt{14}< \sqrt{25}+\sqrt{9}=5+3=8\)
Vì \(9>8\) nên \(4+\sqrt{33}>\sqrt{29}+\sqrt{14}\)
Vậy \(4+\sqrt{33}>\sqrt{29}+\sqrt{14}\)
Sorry nhầm !!!! làm tại
\(\sqrt{29}+\sqrt{14}< \sqrt{33}+\sqrt{16}=\sqrt{33}+4\)
Vậy \(\sqrt{33}+4>\sqrt{29}+\sqrt{14}\)
so sanh 4+\(\sqrt{33}\)va \(\sqrt{29}\)+\(\sqrt{14}\)
=3.74165738 chac 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000%
So sánh:
a) 4 + \(\sqrt{33}\) và \(\sqrt{29}\) + \(\sqrt{14}\)
b) \(\sqrt{48}\)+ \(\sqrt{120}\) và 18
c) \(\sqrt{23}\) + \(\sqrt{15}\)và \(\sqrt{91}\)
4 > căn 14 , căn 33 > căn 29
=> 4+ căn 33 > căn 29 + căn 14
So sánh
a) \(6\) và \(\sqrt{35}\)
b) \(\sqrt{23}+\sqrt{15}\) và \(\sqrt{91}\)
c) \(4+\sqrt{33}\) và \(\sqrt{29}+\sqrt{14}\)
d) \(\sqrt{33}-\sqrt{19}\) và \(6-\sqrt{17}\)
e) \(\sqrt{26}-\sqrt{3}-\sqrt{2009}\) và \(-42\)
g) \(\sqrt{17}+\sqrt{5}+\sqrt{1}\) và \(\sqrt{45}\)
h) \(\sqrt{a}+\sqrt{b}\) và \(\sqrt{a+b}\) với a>= 0; b>= 0
a, Ta có: \(\sqrt{36}=6\)
Vì \(36>35\Rightarrow\sqrt{36}>\sqrt{35}\) hay \(6>\sqrt{35}\)
So sanh: \(4+\sqrt{33}\) va \(\sqrt{29}+\sqrt{14}\)
Ta co:\(4+\sqrt{33}=\approx9,744562647\)
\(\sqrt{29}+\sqrt{14}=\approx9,126822194\)
Vi 9,744562647>9,126822194 nen \(4+\sqrt{33}>\sqrt{29}+\sqrt{14}\)
SO SANH :
4 + \(\sqrt{33}\) va \(\sqrt{29}+\sqrt{14}\)
căn ra số dữ quá *_*!!!!!!!
duyệt đi
Ta có :4+\(\sqrt{33}\) = \(\sqrt{16}+\sqrt{33}\)
Mà \(\sqrt{16}>\sqrt{14},\sqrt{33}>\sqrt{29}\)
Nên \(\sqrt{16}+\sqrt{33}>\sqrt{29}+\sqrt{14}\)
Hay \(4+\sqrt{33}>\sqrt{29}+\sqrt{14}\)
\(\left(5+4\sqrt{2}\right)\left(3+2\sqrt{1+\sqrt{2}}\right)\left(3-2\sqrt{1+\sqrt{2}}\right)\\ \\ \\ \sqrt{\frac{9}{4}-\sqrt{2}}\\ \\ \\ Sosanh2\sqrt{27}va\sqrt{147}\\ \\ \\ 2\sqrt{15}va\sqrt{59}\\ \\ \\ 2\sqrt{2}-1va2\\ \\ \\ \frac{\sqrt{3}}{2}va1\\ \\ \\ -\frac{\sqrt{10}}{2}va-2\sqrt{5}\\ \\ \\ \sqrt{6}-1va3\\ \\ \\ 2\sqrt{5}-5\sqrt{2}va1\\ \\ \\ \frac{\sqrt{8}}{3}va\frac{3}{4}\\ \\ \\ -2\sqrt{6}va-\sqrt{23}\\ \\ \\ 2\sqrt{6}-2va3\\ \\ \\ \sqrt{111}-7va4\)
Xếp theo thứ tự tăng dần: \(21,2\sqrt{7},15\sqrt{3},-\sqrt{123}\) ; \(28\sqrt{2},\sqrt{14},2\sqrt{147},36\sqrt{4}\)
giảm dần: \(6\sqrt{\frac{1}{4}},4\sqrt{\frac{1}{2}},-\sqrt{132},2\sqrt{3},\sqrt{\frac{15}{5}}\); \(-27,4\sqrt{3},16\sqrt{5},21\sqrt{2}\)
a,\(\left(5+4\sqrt{2}\right)\left(3+2\sqrt{1+\sqrt{2}}\right)\left(3-2\sqrt{1+\sqrt{2}}\right)\)
=\(\left(5+4\sqrt{2}\right)\left(9-4\left(1+\sqrt{2}\right)\right)\)
=\(\left(5+4\sqrt{2}\right)\left(9-4-4\sqrt{2}\right)\)
=\(\left(5+4\sqrt{2}\right)\left(5-4\sqrt{2}\right)=25-\left(4\sqrt{2}\right)^2\)
=-7
b, \(\sqrt{\frac{9}{4}-\sqrt{2}}=\sqrt{\frac{9-4\sqrt{2}}{4}}=\frac{\sqrt{9-4\sqrt{2}}}{2}=\frac{\sqrt{9-2\sqrt{8}}}{2}=\frac{\sqrt{\left(\sqrt{8}-1\right)^2}}{2}=\frac{\left|\sqrt{8}-1\right|}{2}=\frac{\sqrt{8}-1}{2}\)
So sánh:
1) \(2\sqrt{27}\) và \(\sqrt{147}\)
+ \(2\sqrt{27}\) = \(6\sqrt{3}\)
+ \(\sqrt{147}\) = \(7\sqrt{3}\)
⇒ \(6\sqrt{3}\) < \(7\sqrt{3}\)
Vậy: \(2\sqrt{27}\)< \(\sqrt{147}\)
2) \(2\sqrt{15}\) và \(\sqrt{59}\)
+ \(2\sqrt{15}\) = \(\sqrt{60}\)
⇒ \(\sqrt{60}\) > \(\sqrt{59}\)
Vậy: \(2\sqrt{15}\) > \(\sqrt{59}\)
3) \(2\sqrt{2}-1\) và 2
\(giống\left(-1\right)\left\{{}\begin{matrix}3-1\\2\sqrt{2}-1\end{matrix}\right.\)
So sánh: 3 và \(2\sqrt{2}\)
+ 3 = \(\sqrt{9}\)
+ \(2\sqrt{2}=\sqrt{8}\)
⇒ \(\sqrt{8}\) < \(\sqrt{9}\)
⇒ \(\sqrt{8}\) -1 < \(\sqrt{9}\) -1
⇒ \(2\sqrt{2}\) - 1 < 3 - 1
Vậy: \(2\sqrt{2}-1< 2\)
4) \(\frac{\sqrt{3}}{2}\) và 1
+ 1 = \(\frac{2}{2}\)
⇒ \(\frac{\sqrt{3}}{2}\) < \(\frac{2}{2}\)
Vậy: \(\frac{\sqrt{3}}{2}\) < 1
5) \(\frac{-\sqrt{10}}{2}\) và \(-2\sqrt{5}\)
+ \(-2\sqrt{5}\) = \(\frac{-4\sqrt{5}}{2}\) = \(\frac{-\sqrt{80}}{2}\)
⇒ \(\frac{-\sqrt{10}}{2}\) > \(\frac{-\sqrt{80}}{2}\)
Vậy: \(\frac{-\sqrt{10}}{2}\) > \(-2\sqrt{5}\)