A curve has the equation y = 2x cos(3x) + (3x^2-4) sin(3x). Find the derivative in the form (mx^2 + n) cos(3x)

y = 2x cos(3x) + (3x2-4) sin(3x)
dy/dx = (2x x -sin(3x) x 3) + (2 x cos(3x)) + (6x sin(3x)) + ((3x2-4) cos(3x) x 3)
dy/dx = -6x sin(3x) + 2 cos (3x) + 6x sin(3x) + (9x2-12) cos(3x)
dy/dx = (9x2-12 + 2) cos (3x) = (9x2-10) cos (3x)
m = 9n = -10

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Answered by Thomas L. Maths tutor

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