Which number produces an irrational number when multiplied by 1/2

Quick answer

Any irrational number. I can't think of any exception to this statement.

sqrt(5) is irrational.  1/2 * sqrt(5) is still irrational.

-sqrt(5) is irrational. -1/2 * sqrt(5) is still irrational

2 + sqrt(5) is irrational. Multiplying this by 1/2 is still irrational.

1/2(2 + sqrt(5) = 1 + 1/2 * sqrt(5) ) is irrational.

Conclusion

There are no exceptions to this.  All irrational numbers produce irrationals when multiplied by 1/2

98 points djdjsi zisksis sjsjsi sisksj sksjdj sksks sjsisj

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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