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
Alex787 [66]
3 years ago
7

Expansion Numerically Impractical. Show that the computation of an nth-order determinant by expansion involves multiplications,

which if a multiplication takes sec would take these times:
n 10 15 20 25
Time 0.004 sec 22 min 77 years 0.5.109years
Mathematics
1 answer:
posledela3 years ago
8 0

Answer:

  • number of multiplies is n!
  • n=10, 3.6 ms
  • n=15, 21.8 min
  • n=20, 77.09 yr
  • n=25, 4.9×10^8 yr

Step-by-step explanation:

Expansion of a 2×2 determinant requires 2 multiplications. Expansion of an n×n determinant multiplies each of the n elements of a row or column by its (n-1)×(n-1) cofactor determinant. Then the number of multiplies is ...

  mpy[n] = n·mp[n-1]

  mpy[2] = 2

So, ...

  mpy[n] = n! . . . n ≥ 2

__

If each multiplication takes 1 nanosecond, then a 10×10 matrix requires ...

  10! × 10^-9 s ≈ 0.0036288 s ≈ 0.004 s . . . for 10×10

Then the larger matrices take ...

  n=15, 15! × 10^-9 ≈ 1307.67 s ≈ 21.8 min

  n=20, 20! × 10^-9 ≈ 2.4329×10^9 s ≈ 77.09 years

  n=25, 25! × 10^-9 ≈ 1.55112×10^16 s ≈ 4.915×10^8 years

_____

For the shorter time periods (less than 100 years), we use 365.25 days per year.

For the longer time periods (more than 400 years), we use 365.2425 days per year.

You might be interested in
one t shirt is sold to every 5 people who attends a concert what is the ratio of people to t shirts sold to
Stolb23 [73]

Answer:

1:5

Hope it help yuh..Mark brianliest if my answer suit your question

4 0
3 years ago
3pqr+6pt+3pqs<br><br><br>factories
Sunny_sXe [5.5K]

3pqr + 6pt + 3pqs \\  = 3p(qr + 2t + qs)

Hope you could understand.

If you have any query, feel free to ask.

5 0
2 years ago
Read 2 more answers
Which is an exponential decay function?
spayn [35]

Answer:

c)3/2(8/7)^x

Step-by-step explanation:

Evaluate the functions. 

1. Because 7/4 > 1 and the exponent is positive,

  the function does not decay.

2.Because 4/5 < 1 and the exponent is negative,

   the function does not decay.

3. Because 8/7 > 1 and the exponent is negative,

   the function decays.

4. Because 9/2 > 1 and the exponent is positive,

   the function does not decay.

A composite plot the functions verifies the answer.

If all the x's are exponents, then 3/2 (8/7)^-x is the only one that decays as x gets bigger.  That's because the base is greater than 1 and the x is negative.

please mark me brainliest :)

5 0
3 years ago
9x - 3y = -2<br> -3x + y = -3
morpeh [17]
Multiply 2nd equation by 3 and add to first
9x-3y=-2
<u>-9x+3y=-9 +</u>
0x+0y=-7

0=-7
false
no solution
these lines aer paraalell so no solution
6 0
3 years ago
Which is closest to the measure of the marked angle in the shape?​
GaryK [48]
Out of the 3 choices, I’d say it’s C.

180 degrees because 180 degrees means a straight line and it’s not close to 90, a right angle. It seems like a closer angle to a straight line.
4 0
3 years ago
Other questions:
  • What is the difference between the reciprocal and the opposite of a fraction? Plz help!
    14·1 answer
  • What is the slope of the line?
    7·2 answers
  • Im struggling on dis now TwT pls halp me<br><br>lateral area<br>surface area <br>volume​
    10·2 answers
  • Triangle ABC is dilated by a scale factor of 4 to form triangle A′B′C′.
    8·1 answer
  • Find the value of two numbers if their sum is 12 and their difference is 4. Systems of equations 8th grade math.
    14·1 answer
  • PLEASE HELP I CAN'T CHOSE BETWEEN B AND D
    15·2 answers
  • If 2^2x=2^3, what is the value of x?<br><br> 2/3<br> 3/2<br> 2<br> 3<br><br> edit: answer is 3/2
    9·1 answer
  • Darryl uses a 56N force to push a boulder off a cliff that is 425m tall. What is the work done on the boulder? Show your work.
    6·1 answer
  • Roy used 1/4 of his money on 3 pens and 6 notebooks. The cost of each pen is 3 times the cost of each notebook. He bought some m
    11·2 answers
  • Find the factor of each ff.<br> 10x²-21x-27​
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!