Representing and, or in equations

[sarahahmed]

hello
how can I represent and in mathematical equations, for example if I want to say if g= Min(x1,x2) and Min (y1, y2)
can I leave and as it is? or I should represent it by other symbol the same thing for "or"

thanks

[min]

g = Min(x1, x2)
is the standard representation when we have 2 numbers to get the lower.
so if x1 <= x2
g = x1

[sarah ahmed]

Ok thanks

[sarah ahmed]

I have another question how can I express the following into mathematical equation?
if x_i=1 and z_i=1
then
[tex]sol=\sum_{i}^{ n} y_i[/tex]
thanks

[Guest]

Please solve my silly but small doubt related to prime numbers as finding prime numbers in numbers greater than 500. How we will know this. Simply a/s to definition or anything else.
Thanks

[Guest]

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These are some of the prime numbers above 500 and these kind of mistakes occur sometimes...so its not a big issue..everyone faces the problems.