Szczegółowe wyjaśnienie:
6x²+7x+2 = (2-3x)(3x+2)
6x²+7x+2 = 4-9x²
15x²+7x-2 = 0
∆= 7²-4*15*(-2)
∆= 49+120
∆= 169
√∆ = 13
x1 = (-7-13)/(2*15) = -20/30 = -2/3
x2 =(-7+13)/(2*15) = 6/30 = 1/5
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1/2 x²-3x+9 =(x-3)(x-5)
1/2 x²- 3x+9 = x²-8x+15
-1/2 x² +5x -6 =0 |* (-2)
x²-10x+12 =0
∆ = (-10)² -4*1*12
∆ = 100-48
∆ = 52
√∆ = √52 = 2√13
x1 = (10-2√13)/2 = 5-√13
x2 = (10+2√13)/2 = 5+√13
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