<span> x</span>³<span>- 6x</span>²<span>-7x+18 |x+2
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- x</span>³+2x²<span> | x</span>²-8x+9
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-8x²- 7x
-(- 8x²-16x)
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9x+18
- (9x+18)
(x²-8x+9)(x+2) = x³-8x²+9x+2x²-16x+18= x³-6x²-7x+18
5 – a/3 – 3 – 2a/5 < 0
2 – a/3 – 2a/5 < 0
30 – 5a – 6a < 0
30 – 11a < 0
– 11a < – 30
a > 30/11 = a > 2 8/11
30/11 ≈ 2,72727