\(\dfrac{1}{3}:\left(\dfrac{1}{6}-\dfrac{1}{2}\right)< =x< =\dfrac{2}{3}\left(-\dfrac{1}{6}+\dfrac{3}{4}\right)\)

=>\(\dfrac{1}{3}:\left(\dfrac{1}{6}-\dfrac{3}{6}\right)< =x< =\dfrac{2}{3}\left(-\dfrac{2}{12}+\dfrac{9}{12}\right)\)

=>\(\dfrac{1}{3}:\dfrac{-2}{6}< =x< =\dfrac{2}{3}\cdot\dfrac{7}{12}\)

=>\(\dfrac{1}{3}\cdot\dfrac{-6}{2}< =x< =\dfrac{14}{24}=\dfrac{7}{12}\)

=>\(-1< =x< =\dfrac{7}{12}\)

=>Chọn A

A

A

Lời giải:
$|x+2|+2|x+2|=3$

$3|x+2|=3$

$|x+2|=1$

$\Rightarrow x+2=1$ hoặc $x+2=-1$

$\Rightarrow x=-1$ hoặc $x=-3$

Vậy có 2 giá trị nguyên của $x$ thỏa mãn 

Đáp án C.

1. A

2. D

3. A

4. A

4A

3A

2D

1D

a: Ta có: \(\left(\dfrac{3}{2}x-\dfrac{1}{5}\right)^2\cdot\left(x^2+\dfrac{1}{2}\right)=0\)

\(\Leftrightarrow x\cdot\dfrac{3}{2}=\dfrac{1}{5}\)

hay \(x=\dfrac{1}{5}:\dfrac{3}{2}=\dfrac{2}{15}\)

b: Ta có: \(\dfrac{x+1}{99}+\dfrac{x+2}{98}+\dfrac{x+3}{97}+\dfrac{x+4}{96}=-4\)

\(\Leftrightarrow x+100=0\)

hay x=-100

Mn nhớ giải chi tiết ra nha

a ,   x = − 61 x = − 132 b ,   x = − 856 x = − 965

Làm là:

(97,6x37+726,9x37)=37x(97,6+726,9)=37x824,5=30506,5.

(96x2-960x0,1+96000x0,001-9,6)=9,6x10x2-9,6x100x0,1+9,6x10000x0,001-9,6=96x20-9,6x10+9,6x10-9,6x1=9,6x(20-10+10-1)=9,6x19=182,4

=30506,5x182,4

=5564385,6

A

A

B

Chọn B