(Х+3)×5=5х+15
(1,4-у)×2=2,8-2у
(2х+1/3)×6=12х+2
А) 1/(2^2*5)=1/(4*5)=1/20
б)1/(2*5^2)=1/(2*25)=1/50
в)1/2^3=1/8
Cosα - cos3α -2sin2αsin(-α)
------------------- = ------------------- = tg2α
sinα - sin3α 2sin(-α)cos2α
1)8-3+4=9
2)7+2-4=5
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