Question

a) 3/14 . 17/15 + 2/15 - 17/15 . 17/14 b) 0,75 - ( 3 1/2 - 2,25 ) + 2 . (-1/2)²

Answer 1

`a) 3 / 14 . 17 / 15 + 2 / 15 - 17 / 15 . 17 / 14`

`= 3 / 15 . 17 / 14 - 17 / 15 . 17 / 14 + 2 / 15`

`= 17 / 14 ( 3 / 15 - 17 / 15 ) + 2 / 15`

`= 17 / 14 . [-14] / 15 + 2 / 15`

`= [-17] / 15 + 2 / 15 = [-15] / 15 = -1`

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`b) 0,75 - ( 3 1 / 2 - 2,25 ) + 2 . ( -1 / 2 )^2`

`= 3 / 4 - ( 7 / 2 - 9 / 4 ) + 2 . 1 / 4`

`= 3 / 4 - ( 14 / 4 - 9 / 4 ) + 1 / 2`

`= 3 / 4 - 5 / 4 + 1 / 2`

`= [-2] / 4 + 1 / 2 = [-1] / 2 + 1 / 2 = 0`