How do you evaluate #\sqrt { 7+ \sqrt { 2} }#?

1 Answer
dansmath
May 14, 2017

The irrational number #sqrt(7+sqrt(2)# is about #2.9#; more accurately it's around #2.90072638529956752086287311525.#

Explanation:

It's already "evaluated," like #pi#, it's a specific real number. I would tell my students to just leave it as an exact value.

If you want an approximation, hit 2 then the √ button, then add 7, then hit the √ button again. You'll find it's about #2.900726385#.

\\ dansmath // strikes again!

Related questions
Impact of this question
1145 views around the world
You can reuse this answer
Creative Commons License