Алгебра 8 класс

1) (5(√3)^2):6
= (5 * 3):6
= 15:6
= 2.5

2) (√5-√8)x(√8+√5)
= (√5 - 2√2)(2√2 + √5)
= (√5 * 2√2 + √5 * √5 - 2√2 * 2√2 - 2√2 * √5)
= (2√10 + 5 - 8 - 2√10)
= (-6)

3) (√8+2)^2
= (√8 + 2)(√8 + 2)
= (√8 * √8 + √8 * 2 + 2 * √8 + 2 * 2)
= (8 + 2√8 + 2√8 + 4)
= (12 + 4√8)
= (12 + 4(2√2))
= (12 + 8√2)

4) 0.7√0.04 - 2/3√81
= 0.7 * 0.2 - (2/3) * 9
= 0.14 - 6
= -5.86

5) 4√3 - 3√75 - 2√48
= 4√3 - 3√(25 * 3) - 2√(16 * 3)
= 4√3 - 3√25 * √3 - 2√16 * √3
= 4√3 - 3 * 5√3 - 2 * 4√3
= 4√3 - 15√3 - 8√3
= (4 - 15 - 8)√3
= -19√3

6) √1.2 * √0.3
= √(1.2 * 0.3)
= √0.36
= 0.6