3. Let $$f(x) = \frac{1}{1 + x^2}$$, $$0 \leq x \leq 1$$ and $$P = \{0, \frac{1}{4}, \frac{1}{2}, \frac{3}{4}, 1\}$$ be a partition of $$[0, 1]$$.

(a) \((7\%)\) Calculate the upper sum \(U(f,p)\) and the lower sum \(L(f,p)\) of \(f\) over the partition \(P\). Rounded the answers to the third decimal place.