Find the derivative of

Let f(x) =


By product rule,




= (5x3 + 3x – 1) + (x – 1)(15x2 + 3)


= 5x3 + 3x – 1 + 15x3 + 3x – 15x2 – 3


= 20x3 – 15x2 + 6x – 4


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