1) (-6 - 2) . (-6 + 2) = -8 . (-4) = 32
2) 627 + 125 + (-627) + |-46| -21 = 125 + 46 - 21 = 150
3) (-25) + 30 + (-16) + 25 + (-4) = 30 + (-20) = 10
4) 75 - 5.(15 - 40) - (-60) = 75 - 75 + 80 + 60 = 140
5) |31 - 17| - |15 - 52| = |14| - |-37| = 14 - 37 = -23
6) 13 - 18 - (-42) - 15 = 13 - 18 + 42 - 15 = 22
3 bài sau hết kiên nhẫn rồi, thông cảm nhé.

7) 369.4.[(- 5) + 4. (-8) ]

=  1476 . [(-5) + (-32)]

=  1476 . -37

=  -54612

8)  + 8

=  8 + 8

= 16
9) 72 : (-6 . 2 + 4)

= 72 : (-12 + 4)

= 72 : (-8)

= -9

D

D

Đáp án là:D

Ta có : (5+5x2+5x3+..+5x4+..+5x60 )

=5x(1+2+...+60)

=5x[(60+1)x60:2]

=5x61x30=5x61x5x6=>chia hết cho 6

\(5+5^2+5^3+5^4+...+5^{60}\)

\(=5.\left(5+1\right)+5^3.\left(5+1\right)+....+5^{49}.\left(5+1\right)\)

\(=5.6+5^3.6+...+5^{49}.6\)

=> \(⋮6\)

\(5+5^2+5^3+...+5^{60}\)

\(=\left(5+5^2+5^3\right)+\left(5^4+5^5+5^6\right)+...+\left(5^{58}+5^{59}+5^{60}\right)\)

\(=5.31+5^4.31+...+5^{58}.31\)

\(\Rightarrow⋮31\)

\(5+5^2+5^3+...+5^{60}\)

\(=\left(5+5^2\right)+\left(5^3+5^4\right)+...+\left(5^{59}+5^{60}\right)\)

\(=5\left(1+5\right)+5^3\left(1+5\right)+...+5^{59}\left(1+5\right)\)

\(=5.6+5^3.6+...+5^{59}.6\)

\(=6\left(5+5^3+...+5^{59}\right)⋮6\)

\(5+5^2+5^3+...+5^{60}\)

\(=\left(5+5^2+5^3\right)+\left(5^4+5^5+5^6\right)+...+\left(5^{58}+5^{59}+5^{60}\right)\)

\(=5\left(1+5+5^2\right)+5^4\left(1+5+5^2\right)+...+5^{58}\left(1+5+5^2\right)\)

\(=5.31+5^4.31+...+5^{58}.31\)

\(=31\left(5+5^4+...+5^{58}\right)⋮31\)

Thôi mik biết đáp án rồi không cần trả lời nữa đâu!

đáp án là D nhé bạn

A

Ta có: \(2^x=\dfrac{1}{4}\cdot\dfrac{2}{6}\cdot\dfrac{3}{8}\cdot\dfrac{4}{10}\cdot\dfrac{5}{12}\cdot...\cdot\dfrac{30}{62}\cdot\dfrac{31}{64}\)

\(\Leftrightarrow2^x=\dfrac{1\cdot2\cdot3\cdot4\cdot...\cdot31}{2\cdot\left(2\cdot3\cdot4\cdot...\cdot31\right)\cdot64}\)

\(\Leftrightarrow2^x=\dfrac{1}{2}\cdot\dfrac{1}{64}=\dfrac{1}{128}\)
\(\Leftrightarrow2^x=\dfrac{1}{2^6}\)

\(\Leftrightarrow2^{x+6}=1\)

\(\Leftrightarrow x+6=0\)

hay x=-6

Vậy: x=-6

`1/4 . 2/6 . 3/8 ... . 30/62 .31/64 =2^x`

`-> (1.2.3....30.31)/(4.6.8....62.64)=2^x`

`-> (1.(2.3...31))/(2.(2.3.4...31).32)=2^x`

`-> 1/(2.32)=2^x`

`-> 1/64=2^x`

`-> 1/(2^6)=2^x`

`-> x=-6`.

1 + 2-3-4+5+6-7-8+9+...+28-29-30+31 + 32

= 1 + (2-3-4+5) + (6-7-8+9) + ...+(28-29-30+31) + 32

= 1 + 0+0+...+0+32

= 1+32

=33

1+2-3-4+5+6-7-8+9+...+28-29-30+31+32?

 ( 1 + 2 - 3 - 4 ) + ( 5 + 6 - 7 - 8 ) + ...... + ( 29 + 30 - 31 - 32 )

=         0             +         0            + ....+           0

= 0

a) Ta có: \(\left(x-1\right)^{x+2}-\left(x-1\right)^{x+4}=0\)

\(\Leftrightarrow\left(x-1\right)^x\cdot\left(x-1\right)^2-\left(x-1\right)^x\cdot\left(x-1\right)^4=0\)

\(\Leftrightarrow\left(x-1\right)^{x+2}\cdot\left[1-\left(x-1\right)^2\right]=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-1=0\\x-1=1\\x-1=-1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\x=2\\x=0\end{matrix}\right.\)

b) Ta có: \(\dfrac{1}{4}\cdot\dfrac{2}{6}\cdot\dfrac{3}{8}\cdot\dfrac{4}{10}\cdot\dfrac{5}{15}\cdot...\cdot\dfrac{30}{62}\cdot\dfrac{31}{64}=2x\)

\(\Leftrightarrow2x=\dfrac{1}{64}\)

hay \(x=\dfrac{1}{128}\)

Có: \(\frac{1}{4}.\frac{2}{6}.\frac{3}{8}.\frac{4}{10}...\frac{30}{62}.\frac{31}{64}=\frac{1}{2.2}.\frac{2}{2.3}.\frac{3}{2.4}...\frac{30}{2.31}.\frac{31}{2.32}=\frac{1}{2}.\frac{1}{2}.\frac{1}{2}...\frac{1}{2}.\frac{1}{2}.\frac{1}{32}\)

\(=\frac{1}{2^{31}.2^5}=\frac{1}{2^{36}}=2^x\)\(\Rightarrow1=2^x.2^{36}=2^{36+x}\)\(\Rightarrow2^{36+x}=2^0\Rightarrow36+x=0\Rightarrow x=-36\)