Find a counterexample for the statement. For every real number N > 0, there is some real number x such that Nx > x.
N=1
for any number \[0<N<1\]
yes in fact\[0<N\le1\]
I enjoyed this problem immensely :)
also you might want to first write the negation of the statement before finding the counterexample!!!!
Statement: For every real number N > 0, there is some real number x such that Nx > x. Negation : There exists a real number N>0 such that for all real numbers x it is true that Nx <= x
and any N in (0,1] works
the negation *is* a counterexample, so proving the negation is finding at least one N :)
I have a feeling @malia667 didnt write the equation exactly asked. It is missig some absolute value symbols!!!
electro, can you show me where you would need an absolute value?
thanks guys :)) n=1 was correct
more to come
\[|Nx|>|x|\] since x is any real number, it could be negative too
it doesnt matter if x is negative
\[5(-3)<-3\]
N=5 and x=-3 the inequality flips
.yes but the counterexample addresses that
it may but there are infinite answers. the question would have no meaning to it
it is true that for all x, Nx > x for N inside (0,1]
the given inequality is false for each and every N
i need to ask another question please :))
it you put an absolute sign, then it'd make sense
yes so the above claim goes wrong too when x<0
no, because it says 'there exists an x '
it didnt say for all x in the original statement
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