Solve: (5x2 + 3x – 1) ( x – 1)

1.	Solve: (5x2 + 3x – 1) ( x – 1)
Answer» Let y = (5x² + 3x – 1) ( x – 1) \(\frac{dy}{dx}\)= (5x² + 3x – 1) \(\frac{d}{dx}\)(x – 1) + (x – 1) \(\frac{d}{dx}\)(5x² + 3x – 1) = (5x² + 3x – 1) + (x – 1) (10x + 3) = 5x² + 3x – 1 + 10x² – 10x + 3x – 3 = 15x² – 4x – 4

Answer»

Let y = (5x² + 3x – 1) ( x – 1)

\(\frac{dy}{dx}\)= (5x² + 3x – 1) \(\frac{d}{dx}\)(x – 1) + (x – 1) \(\frac{d}{dx}\)(5x² + 3x – 1)

= (5x² + 3x – 1) + (x – 1) (10x + 3)

= 5x² + 3x – 1 + 10x² – 10x + 3x – 3

= 15x² – 4x – 4

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