bₙ = 17,5 * (-2)ⁿ b₇ = ?
b₇ = 17,5 * (- 2)⁷ = 17,5 * (- 128) = - 2240
X^2 - x/6 - 2 = 0
D = (-1/6)^2 - 4*1*(-2) = 1/36 + 8 = 289/36
x1 = (1/6 + 17/6)/2 = 18/12 = 3/2,
x2 = (1/6 - 17/6)/2 = -8/6 = -4/3.
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площадь ограниченная [0;2П] =удвоенной площади [0;п]