Question

а)√121 - 10√ 6,4 * √0.1

б)2√5 - √45 + √80

в)2√2 * (√8 - √32)

Answer 1

1)

$sqrt{121}-10sqrt{6,4}*sqrt{0,1}= \ \=11-sqrt{100*6,4*0,1}= \ \=11-sqrt{64}=11-8=3$

 

 

2)

$2sqrt{5}-sqrt{45}+sqrt{80}=2sqrt{5}-sqrt{5*9}+sqrt{16*5}= \ \=2sqrt{5}-3sqrt{5}+4sqrt{5}=3sqrt{5}$

 

 

3)

$2sqrt{2}*(sqrt{8}-sqrt{32})=2sqrt{2*8}-2sqrt{2*32}= \ \=2sqrt{16}-2sqrt{64}=2*4-2*8=8-16=-8$