rational and irrational
- Thread starter rehandae
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It's usually helpful to express Rational Numbers as q/r, where r and q are integers with no common factor.
The first one is just a little algebra.
1 rational number is q/r where q and r are integers with no common factor.
Another rational number is s/t where s and t are integers with no common factor.
q/r + s/t = (qt + sr)/st
Can you conclude that st is an integer?
Can you conclude that qt+sr is an integer?
Given those two conclusions, you're done.
Show us what you get. Do the second one. It requires a bit more thought.
The first one is just a little algebra.
1 rational number is q/r where q and r are integers with no common factor.
Another rational number is s/t where s and t are integers with no common factor.
q/r + s/t = (qt + sr)/st
Can you conclude that st is an integer?
Can you conclude that qt+sr is an integer?
Given those two conclusions, you're done.
Show us what you get. Do the second one. It requires a bit more thought.