Question

2. Calculati:
a) 2V3•V2
b) V5•3V2
c)(-2V7)•V14
d) V6•(-4V3);
e) (-3V3)•(-2V5);
f) (-4V1,2)•V2,5​

Answer 1

$a)2 \sqrt{3} \times \sqrt{2} = 2 \sqrt{3 \times 2} = 2 \sqrt{6}$

$b) \sqrt{5} \times 3 \sqrt{2} = \sqrt{5 \times 2} \times 3 = 3 \sqrt{10}$

$c)( - 2 \sqrt{7} ) \times \sqrt{14} = - 2 \sqrt{98} = - 14 \sqrt{2}$

$d) \sqrt{6} \times ( - 4 \sqrt{3} ) = - 4 \sqrt{18} = - 12 \sqrt{2}$

$e)( - 3 \sqrt{3} ) \times ( - 2 \sqrt{5} ) = 6 \sqrt{15}$

$f)( - 4 \sqrt{1.2} ) \times \sqrt{2.5} = - 4 \sqrt{ \frac{6}{5} } \sqrt{ \frac{5}{2} } = - 4 \sqrt{ \frac{30}{10} } = - 4 \sqrt{3}$