x=3. . Find the other two roots.
Hello aideniscool!
(4x³ - 20x² + 19x + 15) : (x-3) = 4x² - 8x - 5
4x³ - 12x²
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- 8x² + 19x
- 8x² + 24x
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- 5x + 15
- 5x + 15
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0
\(4x^2-8x-5=0\\ x^2-2x-1.25=0\\ x=1\pm \sqrt{1+1.25}\\ x\in\{1-1.5,1+1.5\}\\ \color{blue}x\in\{-0.5,2.5\}\)
!