F ' ( X) = 3X^2 - 18X + 15
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3X^2 - 18X + 15 = 3 * ( X^2 - 6X + 5 )
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X^2 - 6X + 5 = 0
D = 36 - 4*1*5 = 16
V D = 4
X1 = ( 6 + 4 ) : 2 = 5
X2 = 1
--------------------
При Y = 0
X1 = 5
X2 = 1
--------------------
X = 0
Y = 5
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<span>Понадобится, приблизительно,7 ложек
220/30=7.33333 ~ 7</span>
22, 27, 29, 72, 77, 79, 92, 97, 99.