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whichscore
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 21 Nov 2010, 10:20
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the maximum possible value of ab ?
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 21 Nov 2010, 10:25
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whichscore
Here i have another question,
If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the maximum possible value of ab ?

As product of two negative numbers is positive then in order to find the answer we should consider the product of max positive values of a and b as well as min negative values of a and b:

If a=3 and b=5 then ab=15;
If a=-4 and b=-4 then ab=16;

So max possible value of av is 16.
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 21 Nov 2010, 10:29
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always impressed by the quickness of your responses !
thanks Bunnel !
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 21 Nov 2010, 14:20
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using formulae
---------------------> -ve * -ve = +ve
--------------------->-ve * 1ve = -ve

max possible value = (-4) * (-4) = 16
min possible value = (-4) * (5) = -20
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 22 Nov 2010, 11:57
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The answer is 16 (-4 *-4 ) >(5*3)
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 22 Nov 2010, 19:44
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whichscore
Here i have another question,
If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the maximum possible value of ab ?

When looking for maximum/minimum value of an expression having multiple variables, check for all combinations of extreme values:

Maximum value of ab: Will be positive so check two cases: (-4)(-4) and (3)(5)
Minimum value of ab: Will be negative with maximum absolute value so check two cases: (-4)(5) and (3)(-4)

Similarly, think what will be the maximum/minimum values of a - b?
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 19 Jun 2017, 13:44
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You can fall into trap if you do not cross check the signs of the equation.

Please note, when you multiply a -ve number with a -ve number the product is positive.

In this case, take both the maximum integers for a & b, which is (3) * (5) = 15

Also, take least numbers - Because both are negative we can compare the positive outcome with the above, hence, (-4) * (-4) = 16

So, 16 is the correct answer.

Principal on which this question is based is = -ve * -ve = +ve
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If a and b are integers and -4=< a =< 3 and -4 =< b =< 5 what is the 08 Feb 2022, 12:35
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