Oblicz:
a) √28∙√63 = ? b) (√3+ 2√2)(4√3-√2) = ?
źródło:
\sqrt{28}*\sqrt{63}=
=\sqrt{4*7}*\sqrt{9*7}=2\sqrt7*3\sqrt7=6*7=42
b) (\sqrt3+2\sqrt2)(4\sqrt3-\sqrt2)=12-\sqrt6+8\sqrt6-4=7\sqrt6+8
a) \sqrt{28}*\sqrt{63}=\sqrt{4*7}*\sqrt{9*7}=2\sqrt7*3\sqrt7=6*7=42 b) (\sqrt3+2\sqrt2)(4\sqrt3-\sqrt2)=4*3-\sqrt6+8\sqrt6-2*2=8+7\sqrt6