Icebreaker
I'm trying to show the following:
Let a^n+b^n=c^n where a, b, c are not equal to zero. There is no real solution for a, b, c as n\rightarrow\infty.
Proof:
Assume the contrary. If there is a real solution for a, b, c as n\rightarrow\infty, then
lim_{n\rightarrow\infty} \frac{a^n+b^n}{c^n}=1
must also be true.
We can use properties of limits and algebra to obtain, from the previous equation
lim_{n\rightarrow\infty} \frac{a^n}{c^n}+lim_{n\rightarrow\infty} \frac{a^n}{c^n}=1
It can be shown that if a^n+b^n=c^n (where a, b, c are not equal to zero) is true, then c>a and c>b
Therefore
0<\frac{a}{c}<1 and 0<\frac{b}{c}<1
Using properties of limits, we can state that
lim_{n\rightarrow\infty} \frac{a^n}{c^n} = lim_{n\rightarrow\infty} \frac{b^n}{c^n} = 0
and therefore
lim_{n\rightarrow\infty} \frac{a^n}{c^n}+lim_{n\rightarrow\infty} \frac{a^n}{c^n}=lim_{n\rightarrow\infty} \frac{a^n+b^n}{c^n}=0
Which is not 1, and we have thus shown that the contrary to the first statement cannot be true.
p.s. I hate tex
Let a^n+b^n=c^n where a, b, c are not equal to zero. There is no real solution for a, b, c as n\rightarrow\infty.
Proof:
Assume the contrary. If there is a real solution for a, b, c as n\rightarrow\infty, then
lim_{n\rightarrow\infty} \frac{a^n+b^n}{c^n}=1
must also be true.
We can use properties of limits and algebra to obtain, from the previous equation
lim_{n\rightarrow\infty} \frac{a^n}{c^n}+lim_{n\rightarrow\infty} \frac{a^n}{c^n}=1
It can be shown that if a^n+b^n=c^n (where a, b, c are not equal to zero) is true, then c>a and c>b
Therefore
0<\frac{a}{c}<1 and 0<\frac{b}{c}<1
Using properties of limits, we can state that
lim_{n\rightarrow\infty} \frac{a^n}{c^n} = lim_{n\rightarrow\infty} \frac{b^n}{c^n} = 0
and therefore
lim_{n\rightarrow\infty} \frac{a^n}{c^n}+lim_{n\rightarrow\infty} \frac{a^n}{c^n}=lim_{n\rightarrow\infty} \frac{a^n+b^n}{c^n}=0
Which is not 1, and we have thus shown that the contrary to the first statement cannot be true.
p.s. I hate tex
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