Simplify this division of square roots?

((sqrt2)/2)/(1+(sqrt2)/2)

3 Answers
Sep 1, 2016

sqrt2-1.

Explanation:

The Expression=(sqrt2/2)/(1+sqrt2/2)

=(sqrt2/cancel2)/((2+sqrt2)/cancel2)

=sqrt2/(2+sqrt2)

=sqrt2/(2+sqrt2)

=cancel(sqrt2)/(cancelsqrt2(sqrt2+1)

=1/(sqrt2+1)xx((sqrt2-1)/(sqrt2-1))

=(sqrt2-1)/(2-1)

=sqrt2-1.

Sep 1, 2016

(sqrt(2)/2)/(1+sqrt(2)/2)=sqrt(2)-1

Explanation:

We will continue under the assumption that "simplifying" requires rationalizing the denominator.

First, we can remove fractions from the numerator and denominator by multiplying both by 2:

(sqrt(2)/2)/(1+sqrt(2)/2) = (sqrt(2)/2)/(1+sqrt(2)/2)*2/2

= sqrt(2)/(2+sqrt(2))

Then, we rationalize the denominator by multiplying by the conjugate of the denominator, and taking advantage of the identity (a+b)(a-b)=a^2-b^2

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

=(2sqrt(2)-sqrt(2)*sqrt(2))/(2^2-sqrt(2)^2)

=(2sqrt(2)-2)/(4-2)

=(cancel(2)(sqrt(2)-1))/cancel(2)

=sqrt(2)-1

Sep 1, 2016

sqrt2-1

Explanation:

We will make use of the fact that (a/b)/(c/d) = (axxd)/(bxxc)

But before we can do that, we need to add the fractions in the denominator to make one fraction.

(sqrt2/2)/(1+sqrt2/2)" = " (sqrt2/2)/((2+sqrt2)/2)

(color(red)(sqrt2)/color(blue)(2))/(color(blue)((2+sqrt2)/color(red)(2))) " = "(color(red)(cancel2sqrt2))/ (color(blue)(cancel2(2+sqrt2)) Much better!

Now rationalise the denominator:

sqrt2/((2+sqrt2)) xxcolor(lime)(((2-sqrt2))/((2-sqrt2))) = (2sqrt2-sqrt2^2)/(2^2 - sqrt2^2)

(2sqrt2-2)/(4 - 2) = (cancel2(sqrt2 -1))/cancel2

=sqrt2 -1