## anonymous one year ago one more question about irrational numbers.

1. anonymous

2. anonymous

Its is 4 Because Pi, is already stated as an irrational number already. without calculation

3. anonymous

I have to figure out if each one is irrational or rational

4. mathmath333

a rational number can be written as $$a/b$$ where a and b are integers

5. phi

another clue is if you write the number as a decimal, you can predict the digits. for example, pi is irrational because we have to calculate each digit in its decimal. Knowing pi= 3.14159 does not tell us what the next digit is. (People have calculated this out to millions of digits... no pattern) on the other hand 1/7 = 0.142857142857142857... (it keeps repeating 142857...) that means it is rational

6. phi

almost all "roots" (example sqrt(2) ) are irrational except for perfect squares such as sqrt(4) = 2.0 (and here we know its decimals.. all 0's)

7. phi

so if you see a fraction of integers, it is rational if you see an irrational number times or divided by a nice number, it stays irrational the only time I can think of to get a rational number from irrationals is if we see for example, $\frac{\pi}{\pi} = 1$

8. anonymous

so my answers I got was 1=rational 2=irrational 3=rational 4=irrational

9. phi

yes, looks good

10. anonymous

ok thank you