Imaginary Numbers

Simplify the imaginary number:  $i^{25}$  .

•  $-i$  

•  $i$  

•  $i^5$  

•  $-1$  

Tags

CCSS.HSN.CN.A.2

Write the numbers using the imaginary unit,  $i$  :  $\sqrt{-90}$  

•  $9i$  

•  $3i\sqrt{10}$  

•  $i\sqrt{90}$  

•  $9i\sqrt{10}$  

 $\left(4-2i\right)-\left(2+6i\right)$  Simpiify. Write your final answer in standard form:

•  $2-8i$  

•  $2-8i^2$  

•  $8-12i^2$  

•  $2+4i$  

Tags

CCSS.HSN.CN.A.2

Simplify. Write your final answer in standard form:  $\left(-1+2i\right)\left(1-3i\right)$  .

•  $5+5i$  

•  $-1+5i-6i^2$  

•  $5+6i$  

•   $-1-6i^2$  

Tags

CCSS.HSN.CN.C.8

Find the discriminant of each quadratic equation, then state the number and type of solutions:  $y=-3x^2+4x-2$  .

• -8, two complex solutions

• -8, one real solution and one complex solution

• 40, two real solutions

• -20, two complex solutions

Tags

CCSS.HSA-REI.B.4B

Solve the equation by taking square roots:  $5x^2=125$  

•  $x=5$  

•  $x=\pm5$  

•  $x=\pm2.236$  

•  $x=10$  

Tags

CCSS.HSA-REI.B.4B

Show the final two steps to solving the equation using the quadratic formula:  $y=x^2-4x+68$  .

•  $\frac{4\pm16i}{2}$  ,  $2\pm8i$  

•  $\frac{4\pm\sqrt{256}}{2}$  , $2\pm8i$  

•  $\frac{4\pm16i}{2}$  ,  $10\ and\ -6$  

•  $\frac{4\pm16}{2}$  , $2\pm8$  

Tags

CCSS.HSA-REI.B.4B

CCSS.HSN.CN.C.7