Solve (2/5x^3+2x-1)+(1/5x^3-9x+2/3)

$$( \frac{ 2 }{ 5 } { x }^{ 3 } +2x-1)+( \frac{ 1 }{ 5 } { x }^{ 3 } -9x+ \frac{ 2 }{ 3 } )$$

Evaluate

$$\frac{3x^{3}}{5}-7x-\frac{1}{3}$$

Solution Steps

Combine \frac{2}{5}x^{3} and \frac{1}{5}x^{3} to get \frac{3}{5}x^{3}.

$$\frac{3}{5}x^{3}+2x-1-9x+\frac{2}{3}$$

Combine 2x and -9x to get -7x.

$$\frac{3}{5}x^{3}-7x-1+\frac{2}{3}$$

Add -1 and \frac{2}{3} to get -\frac{1}{3}.

$$\frac{3}{5}x^{3}-7x-\frac{1}{3}$$

Factor

$$\frac{9x^{3}-105x-5}{15}$$

Solution Steps

Factor out \frac{1}{15}. Polynomial 9x^{3}-105x-5 is not factored since it does not have any rational roots.

$$\frac{9x^{3}-105x-5}{15}$$