Question #03d75

1 Answer
Sep 2, 2017

frac(1 + 2 x^(2) sqrt(x^(2) + 1))(2 (x^(2) + 1))

Explanation:

We have: frac((x^(2) + 1)^(- 1))(2) + frac(x^(2))(sqrt(1 + x^(2)))

= frac(frac(1)(x^(2) + 1))(2) + frac(x^(2))(sqrt(x^(2) + 1))

= frac(1)(2 (x^(2) + 1)) + frac(x^(2))(sqrt(x^(2) + 1))

Let's rationalise the denominator of the second fraction:

= frac(1)(2 (x^(2) + 1)) + frac(x^(2) sqrt(x^(2) + 1))(x^(2) + 1)

= frac(1)(2 (x^(2) + 1)) + frac(2 x^(2) sqrt(x^(2) + 1))(2 (x^(2) + 1))

= frac(1 + 2 x^(2) sqrt(x^(2) + 1))(2 (x^(2) + 1))