4.8. Өрнектерді ықшамдаңдар: 1) (√15+3√5)²−30√3; 2) (√(4−√7)+√(√7+4))²; 3) (√(5−2√6)+√(5+2√6))²; 4) (√(6+√11)−√(6−√11))².

1. \((\sqrt{15}+3\sqrt5)^2=15+45+6\sqrt{75}=60+30\sqrt3\). Азайтсақ, нәтиже \(60\).
2. \((\sqrt{4-\sqrt7}+\sqrt{4+\sqrt7})^2=8+2\sqrt{(4-\sqrt7)(4+\sqrt7)}=8+2\sqrt9=14\).
3. \((\sqrt{5-2\sqrt6}+\sqrt{5+2\sqrt6})^2=10+2\sqrt{25-24}=12\).
4. \((\sqrt{6+\sqrt{11}}-\sqrt{6-\sqrt{11}})^2=12-2\sqrt{36-11}=12-10=2\).

Жауабы: 1) 60; 2) 14; 3) 12; 4) 2.