What does this simplify to?

[MrCodeDude]

(sq.rt (2 - sq.rt(2))) * (sq.rt (2 + sq.rt(2)))

I keep getting, 2 + sq.rt (2). But that is the wrong answer This was part of a question on the test I just failed
-- mrcodedude

 

[Bignate603]

I get 6 but give me a few minutes to look it over

 

[Bignate603]

ok, now I'm thinking square root of 6, can any body else verify?

 

[MrCodeDude]

The decimal answer is 1.41421356237
-- mrcodedude

 

[MrCodeDude]

Bump. I think everyone failed the test, there was an easier way to forget the answer but I forgot the other formula. I wasn't 100% sure whether or not it was correct.
-- mrcodedude

 

[FeathersMcGraw]

Originally posted by: MrCodeDude
The decimal answer is 1.41421356237

Which is the same as saying sqrt(2).

Here's a hint: sqrt(a) * sqrt(b) = sqrt(a * b).

 

[Ranger X]

sqrt of 2

 

[notfred]

It's just the square root of two.

 

[MrCodeDude]

Originally posted by: Ranger X
sqrt of 2

I wish I knew that on the test ! No calculators were allowed or else I would have been able to determine the decimal. Thanks though
-- mrcodedude

 

[Syringer]

(a-b) * (a+b) = a^2 - b^2

so, let a = 2, b = sqrt(2)

then, 2^2 - sqrt(2)^2

= 4 - 2

= 2

And since it's the sqrt of it, it's sqrt 2.

 

[usas423]

no freakin CLUE

 

[Bound_Vortex]

(sqrt(2-sqrt(2)))*(sqrt(2+sqrt(2))) = sqrt ((2-sqrt(2))*(2+sqrt(2))
= sqrt (4 +2*sqrt(2) - 2*sqrt(2) -2) = sqrt (4-2) = sqrt (2)

 

[sash1]

its a simple difference of squares

remove the sq.rt.s for a second

2-sq.2 * 2+sq.2
thats 4 - sq.2^2
which is 4-2
which is just 2

now put back the sq.rt and you have sq.rt of 2!!

~Aunix