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
Nataly [62]
3 years ago
14

Please please please help

Mathematics
1 answer:
Eduardwww [97]3 years ago
7 0

Answer:

I. B. true

II. A true

Step-by-step explanation:

we can use the quadratic equation:

x=\frac{-b+-\sqrt{b^{2}-4*a*c}}{2*a}

we have:

1)x^{2} -4x+5

a=1 b=-4 c=5

x=\frac{-(-4)+-\sqrt{(-4)^{2}-4*1*5}}{2*1} \\\\x=\frac{4+-\sqrt{-4}}{2} \\\\x=\frac{4+-\sqrt{4} i}{2}\\\\x=\frac{4+-2i}{2} \\\\x_{1} =2-i\\\\x_{2} =2+i

the quadratic expression has two complex factors.

2)x^{2} -5x+14

a=1 b=-5 c=14

x=\frac{-(-5)+-\sqrt{(-5)^{2}-4*1*14}}{2*1} \\\\x=\frac{5+-\sqrt{-31}}{2} \\\\x=\frac{5+-\sqrt{31} i}{2}\\\\x_{1} =\frac{5-\sqrt{31}i }{2}\\ \\x_{2} =\frac{5+\sqrt{31}i }{2}

the solution of x^{2} -5x+14 are

x_{1} =\frac{5-\sqrt{31}i }{2}\\\\or\\x_{2} =\frac{5+\sqrt{31}i }{2}

3)2x^{2} -8x+5

a=2 b=-8 c=5

x=\frac{-(-8)+-\sqrt{(-8)^{2}-4*2*5}}{2*2} \\\\x=\frac{8+-\sqrt{24}}{4} \\\\x=\frac{8+-2\sqrt{6}}{4}\\\\x_{1} =2-\frac{\sqrt{6}}{2}\\ \\x_{2} =2+\frac{\sqrt{6}}{2}

You might be interested in
Divde 3/4÷5/7 what was the error 5/7÷3/4=5/7*4/3=20/21
Setler79 [48]

instead of changing the 5/7 u change the 3/4

7 0
3 years ago
Por favor ayudenme a resolverlo
alukav5142 [94]
I dont know that language
6 0
3 years ago
Answer for any of these will help with work as well
Orlov [11]
13. 81.64
14. 803.84
15. 153.83
16. 753.6


you just use circumference and area formulas for a circle
8 0
4 years ago
Evaluate the expression solve for s = -1
Stels [109]

Answer:

16.7

Step-by-step explanation:

48(-1) + 32.7 - 32(-1)

-48+32.7+32

5 0
3 years ago
Read 2 more answers
Suppose X, Y, and Z are random variables with the joint density function f(x, y, z) = Ce−(0.5x + 0.2y + 0.1z) if x ≥ 0, y ≥ 0, z
kompoz [17]

a.

f_{X,Y,Z}(x,y,z)=\begin{cases}Ce^{-(0.5x+0.2y+0.1z)}&\text{for }x\ge0,y\ge0,z\ge0\\0&\text{otherwise}\end{cases}

is a proper joint density function if, over its support, f is non-negative and the integral of f is 1. The first condition is easily met as long as C\ge0. To meet the second condition, we require

\displaystyle\int_0^\infty\int_0^\infty\int_0^\infty f_{X,Y,Z}(x,y,z)\,\mathrm dx\,\mathrm dy\,\mathrm dz=100C=1\implies \boxed{C=0.01}

b. Find the marginal joint density of X and Y by integrating the joint density with respect to z:

f_{X,Y}(x,y)=\displaystyle\int_0^\infty f_{X,Y,Z}(x,y,z)\,\mathrm dz=0.01e^{-(0.5x+0.2y)}\int_0^\infty e^{-0.1z}\,\mathrm dz

\implies f_{X,Y}(x,y)=\begin{cases}0.1e^{-(0.5x+0.2y)}&\text{for }x\ge0,y\ge0\\0&\text{otherwise}\end{cases}

Then

\displaystyle P(X\le1.375,Y\le1.5)=\int_0^{1.5}\int_0^{1.375}f_{X,Y}(x,y)\,\mathrm dx\,\mathrm dy

\approx\boxed{0.12886}

c. This probability can be found by simply integrating the joint density:

\displaystyle P(X\le1.375,Y\le1.5,Z\le1)=\int_0^1\int_0^{1.5}\int_0^{1.375}f_{X,Y,Z}(x,y,z)\,\mathrm dx\,\mathrm dy\,\mathrm dz

\approx\boxed{0.012262}

7 0
3 years ago
Other questions:
  • Can anyone solve this? I'm having a hard time
    11·2 answers
  • Emily has $3.15 worth of dimes and quarters. She has twice as many dimes as quarters. Determine the number of dimes and the numb
    14·1 answer
  • Elena and her sister are sharing the cost of a digital camera. The camera costs $88.50. If Elena saved $50 to buy the camera, ho
    6·1 answer
  • Which graph represents a function, f(x), that has a slope of 3 units and f(0) = 14?
    13·1 answer
  • Find the 114th term of the following sequence
    9·1 answer
  • Micah has a loan of $6,720. This loan has a simple interest rate of 3.5% per year. What is the amount of interest that Micah wil
    6·1 answer
  • HELP PLS!!! BRAINLIEST WILL BE GIVEN​
    7·1 answer
  • −16.2=x−(−9.3) HELLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLPP
    6·2 answers
  • HELPPP ASAP PLEASEEE THANK YOU
    15·1 answer
  • Write an expression that has the same value of 5 to the power of 4
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!