Solving Higher Order Equations by Factoring and Complex #s

 Solve the following equation:

 $x^4\ -x^2-20\ =\ 0$  

•  $\pm2\ and\ \pm10$  

•  $\pm\sqrt{5}\ and\ \pm2i$  

•  $\pm4\ and\ \pm5$  

•  $\pm1\ and\ \pm20$  

Tags

CCSS.HSA-REI.B.4B

Solve:

 $5x^4\ +\ 40x\ =\ 0$  

•  $\pm8\ and\ \pm5$  

• 0,  $8\ and\ \ \left(2\pm5i\sqrt{3}\right)$  

•  $\pm2\ and\ \pm i\sqrt{3}$  

•  $0,\ -2,\ and\ \left(1\pm i\sqrt{3}\right)$  

Tags

CCSS.HSA-REI.B.4B

Solve:

 $2x^3-4x^2+7x=14$  

• 2 and  $\pm\frac{i\sqrt{14}}{2}$  

• 0 and  $2\pm\frac{i\sqrt{7}}{2}$  

•  $-\frac{7}{2}\ ,\ 0,\ and\ 3\sqrt{3}$  

•  $0\ and\ \pm2i\sqrt{7}$  

Tags

CCSS.HSA-REI.B.4B

Solve:

 $3x^5-9x^3-162x=0$  

•  0,  $\pm3\ and\ \pm6$  

• 0,  $\pm3\ and\ \pm i\sqrt{6}$  

• 0,  $\pm3i\ and\ \pm3i\sqrt{2}$  

•  $3,\ \pm9,\ and\ \pm6i$  

Tags

CCSS.HSF-IF.C.7C

What happens when we multiply complex conjugates?

• The result is always 0

• We get a complex result

• The earth explodes

• We get a real result

Tags

CCSS.HSN.CN.C.8

Perform the following operation and simplify:

 $\sqrt{-4}\cdot\sqrt{-9}$  

• 6

• -6

• 6i

• -36i

Tags

CCSS.HSN.CN.A.2

Perform the operation and simplify: (2-9i) - (3-7i)

• -1-2i

• -1-16i

• 57+41i

• -69+13i

Tags

CCSS.HSN.CN.A.2

Perform the following operation and simplify:

 $i^{18}$  

•  $i$  

•  $-i$  

• 1

• -1

Tags

CCSS.HSN.CN.A.2

Perform the operation and simplify: (5+6i)(2-3i)

• 10+15i

• -8-3i

• 28-3i

• 28+3i

Tags

CCSS.HSN.CN.A.2

Perform the operation and simplify:

 $2i^5$  

• 32i

• 2i

• -32i

• -2

Tags

CCSS.HSN.CN.A.2