Q=3:6 = 1/2
b4 = b1*q³ = 6*1/8 = 6/8= 3/4
S5 = b4(q^5-1)/(q-1) =
=3/4*(1/32-1)/(1/2 -1) = 3/4*(-31/32): (-1/2)= 3/4*31/32*2/1)= =93/64
Ответ: 64*S = 64*93/64 = 93
2(5x+3)-1 > 7x-2
10x+6-1 > 7x-2
10x-7x > -2-5
3x > -7
x > -7/3
x > -2 ¹/₃
--------- -2 ¹/₃ -------------------
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x∈(-2 ¹/₃; +∞)