1^2=1;(√50)^2=50
vì 1<50 nên √1<√50hay 1-√50<0
mà 6>0
=> √(1-√50)^2<6
So Sánh:
a 7 + \(\sqrt{5}\) với \(\sqrt{48}+2\)
b \(\sqrt{\left(1-\sqrt{50}\right)^2}\) với 6
Tìm x,y biết: 3x2 - 3xy - 5x - y = -20
Tính:
3(x - 2) -4(2x + 1) - 5(2x + 3) = 50
\(\left(\frac{69}{167}-\left(2+\left(3+\left(4+5^{-1}\right)^{-1}\right)^{-1}\right)^{-1}\right)^{-1}\)
GIÚP MÌNH VỚI MAI NỘP RÒI!!!!!!!!
So sánh hai số x và y
x=\(\left(1-\dfrac{1}{\sqrt{4}}\right)\left(1-\dfrac{1}{\sqrt{16}}\right)\left(1-\dfrac{1}{6\sqrt{36}}\right)\left(1-\dfrac{1}{\sqrt{64}}\right)\left(1-\dfrac{1}{\sqrt{100}}\right)\)
y=0,1
1) \(\left(\dfrac{1}{3}\right)^{50}.90^{25}-\dfrac{2}{3}:4\)
2) \(10.\sqrt{0,01}.\sqrt{\dfrac{16}{9}}+\sqrt{49}-\dfrac{1}{6}.\sqrt{4}\)
so sánh :
a) x = \(\sqrt{961}-\left(\dfrac{1}{\sqrt{6}}-1\right)\) và y =\(\sqrt{1089}-\left(\dfrac{1}{\sqrt{7}}+1\right)\)
\(2\left|2x-6\right|=\dfrac{5}{6}-\left|x-3\right|\)
2:\(\left|x+2013\right|+\left|x+2014\right|+\left|x+2045\right|=2\)
3:\(\left|2x-1\right|=\left|x+1\right|\)
4:\(\sqrt{\left(x+\sqrt{5}\right)}+\sqrt{\left(y-\sqrt{3}\right)^2}+\left|x-y-z\right|=0\)
Thực hiện phép tính sau
a. F=[12(1)-2,3(6)]:4,(21)
b.\(\frac{1\frac{11}{34}.4\frac{3}{7}-\left(\frac{3}{2}-6\frac{1}{3}.\frac{2}{19}\right)}{4\frac{5}{6}+\frac{1}{6}.\left(12-5\frac{1}{3}\right)}\)
c.1-\(\frac{\sqrt{121}}{\sqrt{196}}-\frac{\sqrt{169}}{\sqrt{144}}+\frac{\sqrt{25}}{\sqrt{36}}+\left(-1\frac{2}{3}\right):\left(-3\frac{1}{3}\right)\)
so sánh:
x = \(\left(1-\dfrac{1}{\sqrt{4}}\right)\left(1-\dfrac{1}{\sqrt{16}}\right)\left(1-\dfrac{1}{\sqrt{36}}\right)\left(1-\dfrac{1}{\sqrt{64}}\right)\left(1-\dfrac{1}{\sqrt{100}}\right)\) và y = \(\sqrt{20+0,25}\)
1. Giải \(a,\sqrt{4}-\sqrt{9x}+\sqrt{25x}=8\) \(b,\sqrt{\dfrac{1}{4x}}+\sqrt{\dfrac{1}{9x}}-\sqrt{\dfrac{1}{36x}}=\dfrac{2}{3}\)
2. \(A=\dfrac{1}{\sqrt{1\cdot2018}}+\dfrac{1}{\sqrt{2\cdot2017}}+...+\dfrac{1}{\sqrt{k\left(2018-k+1\right)}}+...+\dfrac{1}{\sqrt{2018\cdot1}}\)
So sánh A với \(2\cdot\dfrac{2018}{2019}\)
3.Cho abc=201. Tính\(\dfrac{201a}{ab+201+a+201}+\dfrac{b}{cb+b+201}+\dfrac{c}{ac+c+1}\)
4.\(B=\left(\dfrac{1-x^3}{1-x}+x\right)\cdot\left(\dfrac{1+x^3}{1+x}-x\right)\) a, Rút gọn B b, tìm x để B=64
5. Tìm x: \(\left|x-2\right|-2\left|x+1\right|=3-2\left(1-2x\right)\)
1 tính
\(\left(-\dfrac{1}{3}+\dfrac{5}{6}\right)^2-\dfrac{\sqrt{25^2-\sqrt{49^2}}}{\sqrt{36^2+\sqrt{38^2}}}\)