=337+829+145-829-337=145

=337+829+145-829-337

=145

=337+829+145-829-337=145

\(\left(-124\right)+15+10+124\)

\(=\left(-124+124\right)+\left(15+10\right)\)

\(=25\)

\(=\left[\left(-124\right)+124\right]+\left(15+10\right)\\ =0+15=15\)

=-124+124+15+10=25

Bài 3:

a: \(=\left(-47+47\right)+\left(200-400\right)=-200\)

b: \(=\left(-2\right)+\left(-2\right)+\left(-2\right)=-6\)

c: \(=25\left(-19-81\right)=25\cdot\left(-100\right)=-2500\)

d: \(=17\cdot28-17\cdot32-28\cdot17+28\cdot32=32\cdot11=352\)

e: \(=12-57+57-12=0\)

2012 . 2013 . 10001 - 2013 . 2012 . 10001 

= 0 

\(145+\left(-217\right)-\left(-318\right)+\left(-783\right)-245+318\)

\(=145-217+318-783-245-318\)

\(=\left(145-245\right)-\left(217+783\right)+\left(318-318\right)\)

\(=\left(-100\right)-1000+0=-1100\)

32*(132-147)+132*(32-247)

=32*(-15)+132*(-215)

=-480+(-28380)

=-28860

lúc đầu tớ làm cho cậu cách cô tớ dạy nhưng tớ k nhớ cách làm nên làm sai nên mới phải chọn cách này

   \(\dfrac{-4}{13}.\dfrac{5}{17}+\dfrac{-12}{13}.\dfrac{4}{17}\)

= \(\dfrac{-4}{13}.\dfrac{5}{17}+\dfrac{-4}{13}.\dfrac{12}{17}\)

= \(\dfrac{-4}{13}.\left(\dfrac{5}{17}+\dfrac{12}{17}\right)\)

= \(\dfrac{-4}{13}.\dfrac{17}{17}\)

= \(\dfrac{-4}{13}.1\)

= \(\dfrac{-4}{13}\)

= \(\dfrac{-4.5-12.4}{13.17}\)

=\(\dfrac{-4\left(5+12\right)}{13.17}\)

=\(\dfrac{-4.17}{13.17}\)

=\(\dfrac{-4}{13}\)

tham khảo:

Ta có :2²⁷= 2^9.3=512³

            : 3¹⁸=3^6.3=729³

2²⁷ = (2³)⁹ = 8⁹

3¹⁸ = ( 3²)⁹ = 9⁹

Vì 9 > 8 nên : 9⁹ > 8⁹

Vậy suy ra: 3¹⁸ > 2²⁷

\(2^{27}=\left(2^3\right)^9=8^9\\ 3^{18}=\left(3^2\right)^9=9^9\\ 8< 9\\ \Rightarrow8^9< 9^9\\ \Rightarrow2^{27}< 3^{18}\)