Question

(4 - raiz quadradra de 13) . (4 - raiz quadradra de 13)

Answer 1

0,39444*0,39444 = 0,15558

Answer 2

$(4 - \sqrt{13}) \cdot (4 - \sqrt{13}) = \\\\ (4 - \sqrt{13})^2 = \\\\ 16 - 4 \sqrt{13} - 4 \sqrt{3} + 13 = \\\\ 16 - 8 \sqrt{13} + 13 = \\\\ \boxed{-8 \sqrt{13} + 29}$