[tex] \frac{\pi}{4} = 45 \: grade[/tex]
[tex] \sin(45) = \frac{ \sqrt{2} }{2} [/tex]
[tex] \frac{ \sqrt{2} }{2 } = \frac{6}{bc} [/tex]
[tex]bc = 6 \sqrt{2} [/tex]
[tex] {ab}^{2} = {bc}^{2} - {ac}^{2} \\ ab = \sqrt{36} = 6[/tex]
