1. Для кого?
2. Над чем?
3. С кем?
<span>(а^2-6ab+9b^2)=(a-3b)^2
(</span><span>4a^2+b^2+4ab)=(2a+b)^2</span>
1) 5√75 - 2√27 = 5√(25*3) - 2√(9*3) = 25√3 - 6√3 = 19√3
2) 3√20 + 5√45 - 2√80 = 3√(4*5) + 5√(9*5) - 2√(16*5) =
= 6√5 + 15√5 - 8√5 = 13√5
3) √176² - (112)²/98 = √(16*11)² - (16*7)²/(49*2) = 16*11 - (16² * 7²)/(7² * 2) =
= 2⁴ *11 - 2⁷ = 2⁴(11 - 2³) = 16*3 = 48
6<span>) √81a + √9a - √49a = 9√a + 3√a - 7√a = 5√a
9) 1/(5+2√6) + 1/(5-2√6) = </span><span>((5-2√6)+</span><span>(5+2√6)) / </span>(5-2√6)*<span><span><span><span>(5+2√6) =
= 10/(5² - (2√6)²) = 10/(25-24) = 10
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