1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
inn [45]
3 years ago
9

Complex root of x^2+3x+9=0

Mathematics
1 answer:
Luden [163]3 years ago
6 0

\text{Quadratic formula}

ax^2+bx+c=0\\\\\Delta=b^2-4ac\\\\x_1=\dfrac{-b-\sqrt\Delta}{2a};\ x_2=\dfrac{-b+\sqrt\Delta}{2a}

-----------------------------------------------------------------------

x^2+3x+9=0\\\\a=1;\ b=3;\ c=9\\\\\Delta=3^2-4(1)(9)=9-36=-27\\\\\sqrt\Delta=\sqrt{-27}=\sqrt{(27)(-1)}=\sqrt{27}\cdot\sqrt{-1}=\sqrt{9\cdot3}i=\sqrt9\cdot\sqrt3i=3\sqrt3i

x_1=\dfrac{-3-3\sqrt3i}{2(1)}=-\dfrac{3}{2}-\dfrac{3\sqrt3}{2}i\\\\x_2=\dfrac{-3+3\sqrt3i}{2(1)}=-\dfrac{3}{2}+\dfrac{3\sqrt3}{2}i


i=\sqrt{-1}

You might be interested in
PLEASE HELP! Will give brainliest! A bag contains 5 pink marbles and 6 green marbles. Two marbles will be selected one at a time
Karolina [17]

Answer:

The selection of the two marbles are <u>dependent</u> because the selection of the pink marble <u>changes</u> the probability that a green marble is drawn next.

If the pink marble had been put back into the bag, the selection of the two marbles would have been <u>independent</u>

======================================================

Explanation:

The key phrase to focus on here is "This marble is placed on a table". It implies that we do not put it back into the bag, and also implies we don't put in a replacement either. Hence we consider this scenario as "no replacement".

In no replacement situations, we always have dependent events. The second selection depends on the first one.

The probability of picking green is 6/11 because there are 6 green out of 5+6 = 11 total. But if we picked a pink one first and didn't put it back, then the 11 drops to 10 and we get 6/10 = 3/5 as the new probability.

In other words,

  • before the pink marble is selected, the chances of green are 6/11
  • after the pink marble is selected, and not put back, the chances of green are now 6/10 = 3/5

Because this probability changes, it's sufficient evidence to say the event of picking green on the second selection is dependent on the first selection of selecting pink.

If the marble had been put back, then we'd revert back to the original state of the bag. That would mean the chances of green would stay at 6/11. Therefore, situations with replacement lead to independent events.

5 0
2 years ago
How do you subtract fractions with like numerators
Mandarinka [93]

Answer:

Step-by-step explanation:

To SUBTRACT fractions with like or the same denominator, just subtract the numerators then copy the common denominator. Always reduce your final answer to its lowest term.

3 0
3 years ago
12u + -8u = -20 solve for u
jekas [21]

u= -5

12u -8u=-20

4u=-20

u=-20/4

u=-5

hopes this helps,

Xeno

7 0
3 years ago
Read 2 more answers
Jen solved the equation to determine the number of questions, x, she answered incorrectly on a test. She began by subtracting 10
fgiga [73]
Answer is Correct. She could have also subtracted 100 from both sides, then divided by .
8 0
3 years ago
Read 2 more answers
Diego can type 140 words in 4 minuets. At this rate, how long will it take him to type 385 words
Ronch [10]
It will take 14 minutes and 8 seconds
4 0
3 years ago
Read 2 more answers
Other questions:
  • The graph represents the atmospheric pressure, in pounds per square inch, as a function of altitude in miles above sea level. Wh
    10·1 answer
  • Item 5Find the percent of the number.175% of 54 is .
    6·1 answer
  • I want to how they answer this question. What is the value of x?
    10·1 answer
  • The main goal of personal financial planning is: saving and investing for future needs. reducing a person's tax liability. achie
    10·1 answer
  • A cyclist rode 3.75 miles in 0.3 hours
    9·1 answer
  • When constructing parallel lines, how can you verify the lines constructed are parallel?t is being constructed based on the mark
    8·1 answer
  • Which expression gives the measure of XYZ?
    11·1 answer
  • Write a real word problem that involves dividing a decimal by a whole number
    10·1 answer
  • 15.
    13·2 answers
  • Can anyone answer these 2?​
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!