4x^2 - 12x - 40 = 0
x^2 - 3x - 10 = 0
(x - 5)(x + 2) = 0
или
4x^2 - 12x + 9 - 49 = 0
(2x - 3)^2 - 49 = 0
((2x - 3)-7)*((2x - 3)+7)=0
(2x - 10)(2x + 4)=0
B1=1,2 , q=4, b3=?
b3=b1.q²
b3=1,2.4²=1,2.16=19,2
b3=19,2
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64y²+16y+1=(8y)²+2*8y+1²=(8y+1)²
27a^2 - 18ab=3a*9a-2b*9a=9a(3a-2b)
Log5(2-x) = log5(x^2)
2-x = x^2
x^2+x-2=0
x = -2
x = 1
ОДЗ: x<2, x <> 0
Ответ: x = 1, x = -2