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Mod versus Rem in Turing |
2013-01-01 |
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From Eric:
I am a teacher teaching computer science using Turing. I am having
difficulty understanding why one would use the mod operator versus the rem
remainder operator.
Mod seems to make the resulting sign depend on the sign of the divisor,
whereas rem makes the resulting sign depend on the dividend.
Examples:
11 mod 5 = 1 and 11 rem 5 =1
-11 mod 5 = 4 and -11 rem 5 = -1
11 mod -5 = -4 and 11 rem -5 =1
-11 mod -5 = -1 and -11 rem -5 = -1
What I can't understand is why this would matter. For example, -11 / 5 =
-2.2 and 11 / -5 = -2.2 get the same result.
So how is a remainder dependent on the sign of one of the parts?
What benefit would using one over the other have?
Any insight would be most helpful!
Eric
Answered by Harley Weston. |
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A triangular island |
2012-12-29 |
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From Udit:
A long time ago Mr Gibson found an island shaped as a triangle with three straight shores of length 3 km,4 km and 5 km. He declared an 'exclusion zone' around his island and forbade anyone to come within 1 km of his shore. What was the area of his exclusion zone?
Answered by Penny Nom. |
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Solve 2x^4+x^3-37x>26x^2+12 using a graphical approach. |
2012-12-29 |
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From Tehmas:
Solve 2x^4+x^3-37x>26x^2+12 using a graphical approach.
I don't know how to find the x-intercepts or y-intercepts in this form.
Answered by Penny Nom. |
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A 12 acre parcel of land |
2012-12-28 |
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From John:
What are the dimensions of a 12-acre parcel if it is 3 square acres deep and 4 square acres wide?
Answered by Penny Nom. |
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6 digit permutations from {1-49} |
2012-12-27 |
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From ange:
how many six digits numbers permutations can be formed with the set {1-49} if no digit is used twice in each permutation??
Answered by Penny Nom. |
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Increasing the size of a gift box |
2012-12-27 |
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From Tehmas:
The dimensions of a gift box are consective positive integers such that the height is the lowest integer and the length is the greatest integer. If the height is increased by 1cm, the width increased by 2 cm, and the length increased by 3 cm, then a larger box is constructed and the volume is increased by 456 cm^3. Determine the dimensions of each box.
Answered by Harley Weston. |
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Two polynomials are divisible by x - 2 |
2012-12-26 |
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From Tehmas:
Determine the values of m and n so that the polynomials 2x^3+mx^2+nx-3 and x^3-3mx^2+2nx+4 are both divisible by x-2.
Answered by Penny Nom. |
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A 4 digit phone lock using the digits 4, 2, 3 and 0 |
2012-12-24 |
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From Ragu:
I would like to know formula for searching a combination of 4 digit. eg.
I knew my Phone Lock combination is my car plate number 4230. But
this time, i used another way around instead of 4230.
But I am sure, there is only this 4 digits only. 4 & 2 & 3 & 0
Answered by Penny Nom. |
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A valid UPC number |
2012-12-22 |
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From Jacob:
A valid UPC number , ABABABABAB- C must end in a 2 after using the rule: 3A +B+3A+B+3A+B+3A+B+3A+B+C=##2. What would term C need to be in order to make the following UPC valid? 2741825293-C
Answered by Harley Weston. |
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The last 4 digits of a cell phone number |
2012-12-22 |
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From Jacob:
If the last 4 digits of a cell phone number, XXX-XXX-ABCD, are restricted where: A cannot be 0 or 1 and B cannot be 0 / how many possible 4 digit combinations are left?
Answered by Penny Nom. |
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2 1/4 x 1/8 x 1 3/4 x 12 4/9 x 3 |
2012-12-21 |
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From Tony:
Ok my question
2 1/4 x 1/8 x 1 3/4 x 12 4/9 x 3
I just can't figure out the question ?
Answered by Penny Nom. |
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3x6)+(12divided by2)-8= ? |
2012-12-17 |
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From christina:
hi my question that's been bothering me is what's
(3x6)+(12divided by2)-8= ?????
Answered by Penny Nom. |
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Milling round stock to square stock |
2012-12-17 |
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From Bryan:
Question from Bryan:
I want to know what the smallest diameter round is that will make a 3-1/4" square? Is there a formula for that? I am milling round stock into square.
Thank you.
Answered by Harley Weston. |
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An integral |
2012-12-16 |
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From Slavena:
integration of (lnx)^2 / x dx
Answered by Penny Nom. |
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An area bounded by lines |
2012-12-16 |
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From sidra:
find area bounded by functions:
y=x
y=2x
and y=5-x
Answered by Penny Nom. |
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