\(\left\{2^2.30-\left[76-\left(9-3\right)^2\right]\right\}:50\)

\(=\left[2^2.30-\left(76-6^2\right)\right]:50\)

\(=\left[2^2.30-\left(76-36\right)\right]:50\)

\(=\left(2^2.30-40\right):50\)

\(=\left(4.30-40\right):50\)

\(=\left(120-40\right):50\)

\(=80:50\)

\(=\dfrac{8}{5}\)

\(=1,6\)

a) 23 . 17 - 24 . 14

b)90 - {20 + [30 - (25 + 5) - 10}

a) 23 . 17 - 24 . 14

= 8 . 17 - 16 . 14

= 136 - 224

= -88

b) 90 - { 20 + [ 30 - ( 25 + 5 ) - 10 }

= 90 - { 20 + [ 30 - 30 - 10 ] }

= 90 - { 20 + ( -10 ) }

= 90 - 10

= 80

bài 1 : tính

a) 20-[ 30 -( 5-1)2 ] b) 60 :{[(12-3) .2] +2 }

*giúp mình với minh đang cần rất gấp ***

a) 20 - [ 30 - ( 5 - 1 )2 ]

= 20 - [ 30 - 42 ]

= 20 - [ 30 - 16 ]

= 20 - 14

= 6

b) 60 : { [ ( 12 - 3 ) . 2 ] + 2 }

= 60 : { [ 9 . 2 ] + 2 }

= 60 : { 18 + 2 }

= 60 : 20

= 3