Question

упростите выражение 1/(n+k)+2k/(n^2-k^2)+1/(n-k)

Answer 1

n - k + 2k + n + k / (n-k)(n+k) = 2n + 2k / (n-k)(n+k) = 2(n+k) / (n-k)(n+k) = 2/(n-k)