Question

True or false, and explanation please?

If the radius of a circle is irrational, the area must be irrational.

Answer 1

The area of a circle with radius r is

A = pi*r^2

since the pi is present and pi is irrational, it makes A an irrational number

the only way to make A rational is to have the radius r be something like r = 1/sqrt(pi)

Answer 2

Wait so the answer is true because pi is irrational?

Answer 3

yes in general the area is irrational unless the radius is r = 1/sqrt(pi) or something like that

Answer 4

But the question says

"If the radius of a circle is irrational, the area MUST be irrational. "

I think you just offered a counter-example, @jim_thompson5910 :)

Answer 5

regarding the if,then statement....@jim_thompson5910 provides a counter-example so answer is False

Answer 6

LOL @dumbcow , my thoughts exactly. :)

Answer 7

http://in.answers.yahoo.com/question/index?qid=20100119061626AA8smFu

Answer 8

this should help