y = (x^2)sin(3x). Find dy/dx
We need to differentiate x2sin(3x). We know how to differentiate (x2) on its own, and how to differentiate sin(3x) on its own. So we can use the Product rule:
dy/dx = (d/dx(x2))sin(3x) + x2(d/dx(sin(3x))
= (2x)sin(3x) + x2(3cos(3x))
= 2xsin(3x) + 3x2cos(3x)
RD
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