Log3 1/27 - log4 32 = log3 (3^-3) - log2^2 (32^5) = -3*log3 (3) - 5/2*log2 (2) = -3 - (5/2) = -(11/2) = -5,5
2cos(x+п/3)=к3
соs( x+п/3)=k3/2
x+п/3=+-arccos k3/2+2пn
x=+-п/6-п/3+2пn
x²y+xy²-3+x+y+-3xy=(x²y+xy²-3xy)+(x+y-3)=
=xy*(x+y-3)+(x+y-3)=
=(x+y-3)*(xy+1)
4) a) x≠2
5-2x>=0
-2x>=-5
x<=2.5
(-бесконечность;2)и(2;2,5)
б)
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{0.5;2
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