=√12+√50+√75+√80=
= 2√3+5√2+5√3+4√5
√a • √b= √a•b
[tex] \sqrt{6} \times \sqrt{2} + \sqrt{10} \times \sqrt{5} + \sqrt{20} \times \sqrt{4} [/tex]
[tex] \sqrt{18} + \sqrt{50} + \sqrt{80} [/tex]
[tex]3 \sqrt{2} + 5 \sqrt{2} + 2 \sqrt{20} [/tex]
[tex] \sqrt{2} (3 + 5 + 2)[/tex]
[tex]10 \sqrt{2} [/tex]
