Answer: Irrational
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Step-by-step explanation:
Let's assume that pi+1 is rational
If so, then pi+1 = m/n where m and n are integers and n is not zero.
Let's isolate pi
pi+1 = m/n
pi = (m/n) - 1
pi = (m/n) - (n/n)
pi = (m - n)/n
This says that pi is rational, as it's in the form integer/integer. But in reality, pi is irrational. The decimal form of pi goes on forever without any known pattern.
So going back to the assumption where we said "pi+1 is rational", that assumption can't be true. If it were true, then it leads to a contradiction. Therefore, pi+1 is irrational.