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
PilotLPTM [1.2K]
3 years ago
10

Based on the context in paragraph 4, fossil refers to _____.

Mathematics
1 answer:
butalik [34]3 years ago
8 0

fuol next time put the paraghpt too pls

Step-by-step explanation:

You might be interested in
Y=6x^2-12x-210 in graphing form
Harrizon [31]

Graph is attached to this answer!

3 0
3 years ago
Verify that the function u(x, y, z) = log x^2 + y^2 is a solution of the two dimensional Laplace equation u_xx + u_yy = 0 everyw
Daniel [21]

Answer:

The function  u(x,y,z)=log ( x^{2} +y^{2}) is indeed a solution of the two dimensional Laplace equation  u_{xx} +u_{yy} =0.

The wave equation  u_{tt} =u_{xx} is satisfied by the function u(x,t)=cos(4x)cos(4t) but not by the function u(x,t)=f(x-t)+f(x+1).

Step-by-step explanation:

To verify that the function  u(x,y,z)=log ( x^{2} +y^{2}) is a solution of the 2D Laplace equation we calculate the second partial derivative with respect to x and then with respect to t.

u_{xx}=\frac{2}{ln(10)}((x^{2} +y^{2})^{-1} -2x^{2} (x^{2} +y^{2})^{-2})

u_{yy}=\frac{2}{ln(10)}((x^{2} +y^{2})^{-1} -2y^{2} (x^{2} +y^{2})^{-2})

then we introduce it in the equation  u_{xx} +u_{yy} =0

we get that  \frac{2}{ln(10)} (\frac{2}{(x^{2}+y^{2}) } - \frac{2}{(x^{2}+y^{2} ) } )=0

To see if the functions 1) u(x,t)=cos(4x)cos(4t) and 2)    u(x,t)=f(x-t)+f(x+1) solve the wave equation we have to calculate the second partial derivative with respect to x and the with respect to t for each function. Then we see if they are equal.

1)  u_{xx}=-16 cos (4x) cos (4t)

   u_{tt}=-16cos(4x)cos(4t)

we see for the above expressions that  u_{tt} =u_{xx}

2) with this function we will have to use the chain rule

 If we call  s=x-t and  w=x+1  then we have that

 u(x,t)=f(x-t)+f(x+1)=f(s)+f(w)

So  \frac{\partial u}{\partial x}=\frac{df}{ds}\frac{\partial s}{\partial x} +\frac{df}{dw} \frac{\partial w}{\partial x}

because we have  \frac{\partial s}{\partial x} =1 and   \frac{\partial w}{\partial x} =1

then  \frac{\partial u}{\partial x} =f'(s)+f'(w)

⇒ \frac{\partial^{2} u }{\partial x^{2} } =\frac{\partial}{\partial x} (f'(s))+ \frac{\partial}{\partial x} (f'(w))

⇒\frac{\partial^{2} u }{ \partial x^{2} } =\frac{d}{ds} (f'(s))\frac{\partial s}{\partial x} +\frac{d}{ds} (f'(w))\frac{\partial w}{\partial x}

⇒ \frac{\partial^{2} u }{ \partial x^{2} } =f''(s)+f''(w)

Regarding the derivatives with respect to time

\frac{\partial u}{\partial t}=\frac{df}{ds} \frac{\partial s}{\partial t}+\frac{df}{dw} \frac{\partial w}{\partial t}=-\frac{df}{ds} =-f'(s)

then  \frac{\partial^{2} u }{\partial t^{2} } =\frac{\partial}{\partial t} (-f'(s))=-\frac{d}{ds} (f'(s))\frac{\partial s}{\partial t} =f''(s)

we see that  \frac{\partial^{2} u }{ \partial x^{2} } =f''(s)+f''(w) \neq f''(s)=\frac{\partial^{2} u }{\partial t^{2} }

u(x,t)=f(x-t)+f(x+1)  doesn´t satisfy the wave equation.

4 0
3 years ago
Please help me its urgent!!
beks73 [17]

Answer:

Step-by-step explanation:

The correct answer is B. I'm pretty sure about it. Thank you.

4 0
3 years ago
Susan has a 12-inch board for construction a wooden chair. The directions say to use a board that is 29 centimeters long.Is her
steposvetlana [31]
Is would be 1.413 I think
3 0
4 years ago
Number of comments got maxed out so here's another post.
suter [353]
That’s cool. i need p01nts so imma comment
7 0
3 years ago
Other questions:
  • On Monday, stock A's price fell 0.67 and stock B's price fell 0.60. Stock C's price did not fall as much as stock A's, but it fe
    6·1 answer
  • Please help!!!!!!!!!! Me
    8·1 answer
  • Which points lie on the line whose equation is 8x - 2y + 7 = -9? Select all that apply.
    7·1 answer
  • PLZ HELP!!!!!!!!!!!!!!!
    6·1 answer
  • 5. Simplify: 3a + b+ a - 5
    11·1 answer
  • Can someone help me
    6·1 answer
  • Why do economists pay a great deal of attention to the baby boom generation?
    11·1 answer
  • What is mother = mother
    11·2 answers
  • If a/b= (3/7)2 ÷ (9/7)0, then find the value of (b/a)2?<br>pls answer fast​
    10·1 answer
  • Which number line represents the solution of 4x - 9 &gt; - 21?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!