Question

thực hiện phép tính

a, 20 - [ 30- ( 5-1)\(^{^2}\)]

b, ( 39 . 42 - 37 . 42 ) : 42

d, 3\(^{^3}\) : 3\(^{^2}\) + 2\(^{^3}\) . 2\(^{^2}\)

Answer 1

a, 20 - [ 30- ( 5-1)${}^{}$]

= 20 - (30 - 4²)

= 20 - (30 - 16)

= 20 - 14

= 6

b, ( 39 . 42 - 37 . 42 ) : 42

= 42.(39 - 37) : 42

= 39 - 37

= 2

d, 3${}^{}$ : 3${}^{}$ + 2${}^{}$ . 2${}^{}$

= 3 + 2⁵

= 3 + 32

= 35

Answer 2

(39 . 42 - 37 . 42) : 42

= 42 . (39 - 37)

= 42 . 2

= 84

= 84 : 42

= 2

Answer 3

a) 20 - [30 - (5 - 1)²]

= 20 - [30 - 4²]

= 20 - [ 30 - 16]

= 20 - 14

= 6.

b) (39 . 42 - 37 . 42) : 42

= 42 . (39 - 37) : 42

= 42 . 2 : 42

= 84 : 42

= 42.

d) 3³ : 3² + 2³ . 2²

= 3 + 2⁵

= 3 + 32

= 35.

Answer 4