Объем бочки v1 ведра v2 v=πd²/4*h
v1=16*5v2=80v2
80 ведер.
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X-9<_0
x<_9
4+x<_0
x<_ -4
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. -4.. ..........9
x принадлежит[-4;9]
<span>y=-2x+1
x -1 2
y 3 -3
Строим точки и проводим прямую
а)наим у=-3,наиб у=3
б)х∈(0,5;∞)
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