Question

1.Tính:

a. 7 + ( -12 + 43 ) - [ 2 + ( 19 -34 )]

b. 25 + ( - 13 + 8 )

c. ( - 8 ) - [( - 4) + 6 ]

d. ( - 8 ) + 4 - 6

2. Tính nhanh:

( - 321 ) - [( - 321 + 35 ) - 235 ]

 

 

Answer 1

\(a.7+\left(-12+43\right)-\left[2+\left(19-34\right)\right]\)

\(=7+31-\left[2+\left(-15\right)\right]\)

\(=7+31-\left(-13\right)\)

\(=38-\left(-13\right)\)

\(=51\)

\(b.25+\left(-13+8\right)\)

\(=25+\left(-5\right)\)

\(=20\)

\(c.\left(-8\right)-\text{ }\left[\left(-4\right)+6\right]\)

\(=\left(-8\right)-2\)

\(=\left(-10\right)\)

\(d.\left(-8\right)+4-6\)

\(=\left(-4\right)-6\)

\(=\left(-10\right)\)