Answer Happy

Please prove by induction
1 1 1 1 1 + + + n 21. If n E N, then + + 1 1 + ≥1+ - 1 2 3 4 5 2n-1 2n 2 (Note: This problem asserts that the sum of the first 2n terms of the harmonic series is at least 1 + n/2. It thus implies that the harmonic series diverges.) +.