6-4 Solve by Factoring Mixed Practice

Solve:  $x^3-16x=0$  

•  $x=0,\ \pm4$  

•  $x=\pm16$  

•  $x=0,\ +4i$  

•  $x=0,\ \pm i\sqrt{2}$  

Tags

CCSS.HSA-REI.B.4B

Solve:  $x^3+3x^2+2x+6=0$  

•  $x=-4,\ \pm1$  

•  $x=-5,\ \pm i\sqrt{2}$  

•  $x=-4,\ \pm i\sqrt{2}$  

•  $x=-3,\ \pm i\sqrt{2}$  

Tags

CCSS.HSA.APR.B.3

Solve:  $5x^3-16x^2+3x=0$  

•  $x=0,\ -\frac{4}{3},\ 1$  

•  $x=0,\ -\frac{1}{5},\ 1$  

•  $x=0,\ \frac{1}{5},\ -\frac{8}{3}$  

•  $x=0,\ \frac{1}{5},\ 3$  

Tags

CCSS.HSA-REI.B.4B

Solve:  $x^4-9=0$  

•  $x=\pm3$  

•  $x=\pm3i,\ \pm3$  

•  $x=\pm i\sqrt{3},\ \pm\sqrt{3}$  

•  $x=\pm9$  

Solve:  $3x^4-24x^2=0$  

•  $x=0,\ \pm8$  

•  $x=0,\ \pm i\sqrt{2}$  

•  $x=0,\ \frac{5}{8}$  

•  $x=0,\ \pm2\sqrt{2}$  

The correct formula for factoring a difference of cubes  $a^3-b^3$  is 

•  $\left(a-b\right)\left(a^2+ab+b^2\right)$  

•  $\left(a+b\right)\left(a^2-ab+b^2\right)$  

•  $\left(a-b\right)^3$  

•  $\left(a+b\right)\left(a-b\right)$  

Solve:  $8x^3+125=0$  

• $x=-\frac{5}{2},\ \frac{-5\pm5i\sqrt{3}}{4}$

• $x=-\frac{5}{2},\ \frac{5\pm5i\sqrt{3}}{4}$

• $x=-\frac{2}{5},\ \frac{5\pm5i\sqrt{3}}{4}$

• $x=-\frac{2}{5},\ \frac{-5\pm5i\sqrt{3}}{4}$

Solve:  $3x^3-x^2+9x-3=0$  

•  $x=\pm3,\ \frac{1}{3}$  

•  $x=\pm i\sqrt{3},\ \frac{1}{3}$  

•  $x=\frac{1}{3},\ \pm\sqrt{3}$  

•  $x=\pm i\sqrt{3},\ 3$  

Tags

CCSS.HSA.APR.B.3

Solve:  $x^4-10x^2=-9$ 
Hint: is it in standard form? 

•  $x=0,\ \pm3$  

•  $x=\pm i,\ \pm3$  

•  $x=\pm1,\ \pm3$  

•  $x=\pm3i,\ \pm1$  

Solve:  $16x^4=81$ 
Hint: is it in standard form? 

•  $x=\pm3,\ \pm4$  

•  $x=\pm\frac{3}{2},\ \pm\frac{2}{3}$  

•  $x=\pm\frac{3}{2},\ \pm\frac{3}{2}i$  

•  $x=\pm\frac{2}{3},\ \pm\frac{2}{3}i$