Not sure what you want to do......here's the graph : https://www.desmos.com/calculator/0lpspyn1ud
\(f(x)=\sqrt[3]{{x}^{2}+4x}\)
\({f(x)}^{3}={\sqrt[3]{{x}^{2}+4x}}^{3}\)
\({f(x)}^{3}={x}^{2}+4x\)
\({f(x)}^{3}=x(x+4)\)
\(\frac{{f(x)}^{3}}{x}=\frac{x(x+4)}{x}\)
\(\frac{{f(x)}^{3}}{x}=x+4\)
\(\frac{{f(x)}^{3}}{x}-4=x+4-4\)
\(\frac{{f(x)}^{3}}{x}-4=x+0\)
\(\frac{{f(x)}^{3}}{x}-4=x\)
\(x(\frac{{f(x)}^{3}}{x}-4)=x\times x\)
\({f(x)}^{3}-4x=x\times x\)
\({f(x)}^{3}-4x={x}^{2}\)
\({f(x)}^{3}-4x-{x}^{2}={x}^{2}-{x}^{2}\)
\({f(x)}^{3}-4x-{x}^{2}={0x}^{2}\)
\({f(x)}^{3}-4x-{x}^{2}=0\)
\(-{x}^{2}-4x+{f(x)}^{3}=0\)
\(x = {4 \pm \sqrt{(-4)^2-4(-1)({f(x)}^{3})} \over 2(-1)}\)
\(x = {4 \pm \sqrt{16-4(-1)({f(x)}^{3})} \over 2(-1)}\)
\(x = {4 \pm \sqrt{16-(-4)({f(x)}^{3})} \over 2(-1)}\)
\(x = {4 \pm \sqrt{16+4{f(x)}^{3}} \over 2(-1)}\)
\(x = {4 \pm \sqrt{4(4+{f(x)}^{3})} \over 2(-1)}\)
\(x = {4 \pm 2\sqrt{4+{f(x)}^{3}} \over 2(-1)}\)
\(x = {2(2 \pm 1\sqrt{4+{f(x)}^{3}} )\over 2(-1)}\)
\(x = {2(2 \pm \sqrt{4+{f(x)}^{3}} )\over 2(-1)}\)
\(x = {2(2 \pm \sqrt{4+{f(x)}^{3}} )\over -2}\)
\(x = -1(2 \pm \sqrt{4+{f(x)}^{3}} )\)
\(x = -(2 \pm \sqrt{4+{f(x)}^{3}} )\)
\(x = -2 \pm \sqrt{4+{f(x)}^{3}}\)
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