Sкр = <span>πR^2
S = 3.14 * 16.9^2 = 3.14 * 285.61 </span><span>≈ 896.8 (cm^2)
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Решение:
√1,47*1/√300=√(1целая 47/100)*1/√300=√(147/100)*1/√300=√(147/100*300)=√147/30000=√0,0049=0,07
Ответ: 0,07
cos(x)<√3/2
x=-11pi/6+2pik
x=-pi/6+2pik
x=(<span>-11pi/6+2pik;<span>pi/6+2pik) . k=z</span></span>
<span><span> cos(x)≥-1/2</span></span>
<span><span>x=2pi/3+2pik</span></span>
<span><span>x=-2pi/3+2pik</span></span>
<span><span>x=(-2<span><span>pi/3+2pik;2pi/3+2pik) . k=z</span></span></span></span>
Общее:x=[-2pi/3+2pik;-pi/6+2pik)U(pi/6+2pik;2pi/3+2pik] / k=z
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cos(x)≥0
x=pi/2+2pik
x=-pi/2+2pik
x=[-pi/2+2pik;pi/2+2pik] . k=z
sin(x)<-√2/2
x=-3pi/4+2pik
x=-pi/4+2pik
x=(-3pi/4+2pik;-pi/4+2pik) . k=z
Общее: x=[-pi/2+2pik;-pi/4+2pik) . k=z
X+y=5
xy=6
y=5-x x(5-x)=6 -x²+5x-6=0 x²-5x+6=0 по Виетту корни 2 и 3
х=2 у=3
х=3 у=2