1\(а+б)^3
(дробью)
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2sin(2x-π/4)=-√2
sin(2x-π/4)=-√2/2
2x-π/4=(-1)^{n+1}*π/4+πn, n∈Z
2x=(-1)^{n+1}*π/4+π/4+πn, n∈Z
x=(-1)^{n+1}*π/8+π/8+πn/2, n∈Z
Q=b4/b2=4.8/1.2=4
q=4
b1=b2/q=1.2/4=0.3
S8=b1*(1-q^8)/1-q=0.3*(1-65536)/1-4=-19660.5/-3=6553.5
Ответ:S8=6553.5
-3с+6-1,5с-3=-4,5с+3
Если с=-4/9, то -4,5* (-4/9)+3=2+3=5
Ответ: 5