Exponents & order of operations

Question

Use the numbers 1,2,4 and 5 in any order to write expressions to equal each integer from 1 to 20

Answer 1

Here are few examples. You try the rest.

1 = 4 + 2 - (5•1)

2 = 5 - 4 + 2 - 1

3 = 5 - 4 + (2/1)

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10 = 4² - 5 - 1

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16 = 2•(5+1) + 4

17 = (5•4) - 2 - 1

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