=a+3:<span>(a+3)</span><span>^2/<span>(a-3)<span>(a+3) = (сокращаем (a+3))</span></span></span>
4ab - 28b + 8a - 56 = (4ab - 28b) + (8a - 56) = 4b(a - 7) + 8(a - 7) = (a - 7)(4b + 8) = 4(a - 7)(b + 2)
<span>x^4-29x^2+100=0
Пусть t = x^2
t^2 - 29t + 100 = 0
D = 841 - 400 = 441 = 21^2
t1 = (29 + 21)/2 = 25
t2 = (29-21)/2 = 4
t1 = 25 = x^2 => x1 = 5 x2 = -5
t2 = 4 = x^2 => x3 = 2 x4 = -2
Ответ: -5;-2;2;5
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