A) tg5π/4 = tg(π + π/4) = tgπ/4 = 1
б)Сtg4π/3 = Ctg(π + π/3) = Ctgπ/3 = 1/√3
в) tg5π/6 =-1/√3
г) Ctg 7π/4 = Ctg(2π -π/4) = -Ctgπ/4 = -1
см.рис
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-9a6b3z12=-3a2bz4 или (-4z)2b(a)3
а) а-3≥0
|2(а-3)<span>|=2а-6
</span>б)а-3<0
| 2(а-3)<span>| =2(3-а)=6-2а</span>