b)[tex]\sqrt{7^{4}*45+7^{4}*39-7^{4} *3 }[/tex] dam factor comun [tex]7^{4}[/tex]
[tex]\sqrt{7^{4}(45+39-3) } = \sqrt{7^{4}*81 } = 7^{2} + 9 = 58[/tex]
c)[tex]\sqrt{5^{2}*11+19*5^{2} + 5^{2} * 6}[/tex] dam factor comun [tex]5^{2}[/tex]
[tex]\sqrt{5^{2}(11+19+6) } = \sqrt{5^{2}*36 } = 5*6 = 30[/tex]
