Salut!
a)[tex]2\sqrt{3} +5\sqrt{3} -(7\sqrt{3} +2\sqrt{3} )=7\sqrt{3} -9\sqrt{3} =-2\sqrt{3}[/tex]
b)[tex]11\sqrt{7} +7\sqrt{7} -(3\sqrt{7} -5\sqrt{7} )=18\sqrt{7} +2\sqrt{7} =20\sqrt{7}[/tex]
c)[tex]2\sqrt{5} -4\sqrt{5} +(2\sqrt{5} +9\sqrt{5} -7\sqrt{5} )=-2\sqrt{5} +4\sqrt{5} =2\sqrt{5}[/tex]
d)[tex]\sqrt{5} +(-3\sqrt{5} +6\sqrt{5} )-(-3\sqrt{5} -9\sqrt{5})=\sqrt{5} +3\sqrt{5} +12\sqrt{5} =16\sqrt{5}[/tex]
e)[tex]2\sqrt{6} +3\sqrt{3} -(5\sqrt{6} -3\sqrt{3} )+(-3\sqrt{6} -9\sqrt{3} )=-3\sqrt{6} +6\sqrt{3}-3\sqrt{6} -9\sqrt{3} =-6\sqrt{6} -3\sqrt{3}[/tex]
f) [tex](-9\sqrt{13} +5\sqrt{13} )-(8\sqrt{13} -\sqrt{13} )+7\sqrt{11} =-4\sqrt{13} -7\sqrt{13} +7\sqrt{11} =-11\sqrt{13} +7\sqrt{11}[/tex]
g)[tex](3\sqrt{2} -2\sqrt{3} )+(-4\sqrt{2} -3\sqrt{3} )-(6\sqrt{2}-5\sqrt{3} )=-1\sqrt{2}-5\sqrt{3}-6\sqrt{2} +5\sqrt{3} =-7\sqrt{2} + 0=-7\sqrt{2}[/tex]
Sper ca te-am ajutat!
P.S:Coroana?