The derivative of y with respect to x, `dy/dx = 14x^2 + 3x`
`dy/dx = 14x^2 + 3x`
=> `dy = (14x^2 + 3x) dx`
take the integral of both the sides
=> `int dy = int (14x^2 + 3x) dx`
=> `y = 14*x^3/3 + 3x^2/2 + C`
Here, C is a constant; this is included as the derivative of a constant is always 0.
The expression for `y = 14*x^3/3 + 3x^2/2 + C`