let u_0 >0 and ∀n∈N
u_(n+1) =u_n +(1/u_n )
1) prove that (u_n )is increasing and lim u_n =+∞
2)by consideringthe functionϕ(t)=(1/(2t+x))
prove that ∀n∈N Σ_(k=1) ^n (1/(2k+x)) ≤(1/2)ln(1+((2n)/x))
3)find a equivalent of u_n (n→+∞)
If the coordinate of the points A
and B be (3,3) and (7,6) then the
length of the portion of the line
AB intercepted between the axes is
(a) (5/4) (b) ((√(10))/4) (c) ((√(13))/3) (d) none