Question

determinati partea intreaga a lui radical din k2 +k, unde k apartine lui N

Answer 1

$\it \sqrt{k^2+k}=\sqrt{k(k+1)}\\ \\ \sqrt{k\cdot k}<\sqrt{k(k+1)}<\sqrt{(k+1)(k+1)} \Rightarrow k<\sqrt{k(k+1)}<k+1 \Rightarrow\\ \\ \Rightarrow\ \Big[\sqrt{k^2+k}\Big]=k$