find antiderivative of f(x) =4 sqrt(x) -6x^2+3
\(\displaystyle\int(4\sqrt x-6x^2+3)\,\mathrm dx=\int(4x^{1/2}-6x^2+3)\,\mathrm dx=\dfrac{4x^{3/2}}{\frac32}-\dfrac63x^3+3x+C=\dfrac83x^{3/2}-2x^3+3x+C\)
