2. 

\(\left(x\pm\dfrac{4}{3}\right)^{2000}\ge0\forall x\\ =>B\ge105\)

Dấu ''='' xảy ra `<=>` \(x=\mp\dfrac{4}{3}\)

Vậy GTNN `=105<=>` \(x=\mp\dfrac{4}{3}\)

3. \(\left(x+\dfrac{3}{8}\right)^{442}\ge0\forall x\\ =>-\left(x+\dfrac{3}{8}\right)^{442}\le0\\ =>B\le-\dfrac{2}{3}\)

Dấu ''='' xảy ra `<=>x=-3/8`

Vậy GTLN `=-2/3<=>x=-3/8`

307dm=30m7dm

307dm = 30,7 m

307dm = 307dm

tích đúng cho tớ được không

Đáp án là D

sai

125 gì ?

125 gì 

dễ

đk a > 0

\(=\dfrac{4+4\sqrt{a}+a-a+6\sqrt{a}-9}{\sqrt{a}\left(2\sqrt{a}-1\right)}\\ =\dfrac{10\sqrt{a}-5}{\sqrt{a}\left(2\sqrt{a}-1\right)}\\ =\dfrac{5\left(2\sqrt{a}-1\right)}{\sqrt{a}\left(2\sqrt{a}-1\right)}\\ =\dfrac{5}{\sqrt{a}}\)

2/5 x 7/4 - 2/5 x 3/7

= 2/5 x (7/4 - 3/7)

= 2/5 x (49/28 - 12/28)

= 2/5 x 37/28

= 37/70

\(=\dfrac{2}{5}\left(\dfrac{7}{4}-\dfrac{3}{7}\right)\\ =\dfrac{2}{5}\left(\dfrac{49-12}{28}\right)\\ =\dfrac{2}{5}.\dfrac{37}{28}\\ =\dfrac{37}{70}\)

\(a,x-35=120\\ x=120+35\\ x=155\\ b,118-x=310-217\\ 118-x=93\\ x=25\\ c,x+61=156-82\\ x+61=74\\ x=74-61\\ x=13\\ d,x-305=814-712\\ x-305=102\\ x=407\\ e,2x-138=72\\ 2x=72+138\\ 2x=210\\ x=105\\ g,x+35=515:5\\ x+35=103\\ x=68\)