√2 × √4 ÷ √7 = √2 × 2 ÷ √7 = (√2 × 2) / (√7) = (2√2) / (√7) = (2√14) / (√7√7) = (2√14) / (7)
≈1,06904
1)9999+99999=109998
2)1000+999999=1000999
3)100000-999=99001