Answer:
it must also have the root : - 6i
Step-by-step explanation:
If a polynomial is expressed with real coefficients (which must be the case if it is a function f(x) in the Real coordinate system), then if it has a complex root "a+bi", it must also have for root the conjugate of that complex root.
This is because in order to render a polynomial with Real coefficients, the binomial factor (x - (a+bi)) originated using the complex root would be able to eliminate the imaginary unit, only when multiplied by the binomial factor generated by its conjugate: (x - (a-bi)). This is shown below:
![(x-(a+bi))*(x-(a-bi))=\\(x-a-bi)*(x-a+bi)=\\([x-a]-bi)*([x-a]+bi)=\\(x-a)^2-(bi)^2=\\(x-a)^2-b^2(-1)=\\(x-a)^2+b^2](https://tex.z-dn.net/?f=%28x-%28a%2Bbi%29%29%2A%28x-%28a-bi%29%29%3D%5C%5C%28x-a-bi%29%2A%28x-a%2Bbi%29%3D%5C%5C%28%5Bx-a%5D-bi%29%2A%28%5Bx-a%5D%2Bbi%29%3D%5C%5C%28x-a%29%5E2-%28bi%29%5E2%3D%5C%5C%28x-a%29%5E2-b%5E2%28-1%29%3D%5C%5C%28x-a%29%5E2%2Bb%5E2)
where the imaginary unit has disappeared, making the expression real.
So in our case, a+bi is -6i (real part a=0, and imaginary part b=-6)
Then, the conjugate of this root would be: +6i, giving us the other complex root that also may be present in the real polynomial we are dealing with.
Answer:
$214
Step-by-step explanation:
200*0.07 = 14, 200 + 14 = 214
Answer:
21
Step-by-step explanation:
20 x 10 = 200 so 20 students sleep for 9 hours
that leaves 10
since 10 is half of 20, half of 2 is 1 so that last 10 = 1 student,
making 21 students
Answer:
Ron's speed = 3 miles/hour
Stevie's speed = 2.5 miles/hour
On comparing we see Ron is walking faster than Stevie.
Step-by-step explanation:
Given:
Ron takes 10 minutes to walk on a track to cover a distance of 0.5 miles
Stevie takes 6 minutes to walk on a track to cover a distance of 0.25 miles
To find their unit rates in mile per hour and choose the faster one.
Solution:
Unit rate in miles per hour signifies their speeds. Thus, we will find out their speeds.
Ron:
Distance= 0.5 miles
Time = 10 minutes = 
hours
Speed = 
Stevie
Distance = 0.25 miles
Time = 6 minutes = 
hours
Speed = 
Thus, we have
Ron's speed = 3 miles/hour
Stevie's speed = 2.5 miles/hour
On comparing we see Ron is walking faster than Stevie.
Answer:
B
Step-by-step explanation:
