Answer:
The directional derivative of f at A in the direction of [tex]\vec{u}[/tex] AD is 7.
Step-by-step explanation:
Step 1:
Directional of a function f in direction of the unit vector [tex]\vec{u}=(a,b)[/tex] is denoted by [tex]D\vec{u}f(x,y)[/tex],
[tex]D\vec{u}f(x,y)=f_{x}\left ( x ,y\right ).a+f_{y}(x,y).b[/tex].
Now the given points are
[tex]A(8,9),B(10,9),C(8,10) and D(11,13)[/tex],
Step 2:
The vectors are given as
AB = (10-8, 9-9),the direction is
[tex]\vec{u}_{AB} = \frac{AB}{\left \| AB \right \|}=(1,0)[/tex]
AC=(8-8,10-9), the direction is
[tex]\vec{u}_{AC} = \frac{AC}{\left \| AC \right \|}=(0,1)[/tex]
AC=(11-8,13-9), the direction is
[tex]\vec{u}_{AD} = \frac{AD}{\left \| AD \right \|}=\left (\frac{3}{5},\frac{4}{5} \right )[/tex]
Step 3:
The given directional derivative of f at A [tex]\vec{u}_{AB}[/tex] is 9,
[tex]D\vec{u}_{AB}f=f_{x} \cdot 1 + f_{y}\cdot 0\\f_{x} =9[/tex]
The given directional derivative of f at A [tex]\vec{u}_{AC}[/tex] is 2,
[tex]D\vec{u}_{AB}f=f_{x} \cdot 0 + f_{y}\cdot 1\\f_{y} =2[/tex]
The given directional derivative of f at A [tex]\vec{u}_{AD}[/tex] is
[tex]D\vec{u}_{AD}f=f_{x} \cdot \frac{3}{5} + f_{y}\cdot \frac{4}{5}[/tex]
[tex]D\vec{u}_{AD}f=9 \cdot \frac{3}{5} + 2\cdot \frac{4}{5}[/tex]
[tex]D\vec{u}_{AD}f= \frac{27+8}{5} =7[/tex]
The directional derivative of f at A in the direction of [tex]\vec{u}_{AD}[/tex] is 7.
How many solutions does this linear system have? y = 2x – 5 –8x – 4y = –20 one solution: (–2.5, 0) one solution: (2.5, 0) no solution infinite number of solution
Answer:
one solution: (2.5, 0)
Step-by-step explanation:
We are given the following system of equations:
y = 2x - 5
-8x - 4y = -20
Replacing the first equation into the second:
[tex]-8x - 4(2x - 5) = -20[/tex]
[tex]-8x -8x + 20 = -20[/tex]
[tex]-16x = -40[/tex]
[tex]16x = 40[/tex]
[tex]x = \frac{40}{16}[/tex]
[tex]x = 2.5[/tex]
y
[tex]y = 2x - 5 = 2(2.5) - 5 = 5 - 5 = 0[/tex]
Thus the system has one solution: (2.5,0).
there are 24 students in a class. among them 8 are girl.
a.find the ratio of boys and girls
b.find the ratio of girls and boys
Answer:
A 2:1
B 1:2
Step-by-step explanation:
If there is 24 students and 8 are girls, then 24 - 8 tells you how many are boys.
24 - 8 = 16.
There are 16 boys.
If there is 16 boys and 8 girls, the ratio would be 2 : 1 or 2/1 or 2 because 16 and 8 have a common factor of 8, so both sides can be divided by 8.
Hence the 8 : 2.
Ratios are commonly expressed with a colon, so that is going to be the symbol I'm using to differenciate the numbers.
We can just reverse the ratio since the original was boys to girls, but it is now girls to boys.
1:2
2x-3 5x+6= Multiply and combine like terms
Answer:
10x^2 - 3x -18
Step-by-step explanation:
if you meant (2x-3)(5x+6), you just multiply out
Answer:
Step-by-step explanation:
Use FOIL method
(2x - 3)(5x + 6) = 2x*5x + 2x*6 + (-3)*5x + (-3) *6
= 10x² + 12x - 15x - 18 {Combine like terms}
= 10x² - 3x - 18
Like terms are terms that have same variable with same power.
Adar, Chi, and Melissa each left the party by themselves. In how many different orders can they leave?
A. 5
B. 6
C. 7
D. 9
Which expression is equivalent
Answer:
[tex]\sqrt[6]{2\\}[/tex]
Step-by-step explanation:
Rewriting
2 ^1/2 ÷ 2 ^ 1/3
We know a^ b ÷ a^c = a^ (b-c)
2 ^ (1/2 -1/3)
Getting a common denominator
2^ ( 3/6 - 2/6)
2^ 1/6
[tex]\sqrt[6]{2\\}[/tex]
Answer:
[tex]\sqrt[6]{2}[/tex]
Step-by-step explanation:
We can start by writing the expression as one power of two, and then comparing it to the options. The square root of two is the same and [tex]2^{\frac{1}{2} }[/tex] and the cube root of two is the same as [tex]2^{\frac{1}{3} }[/tex]. Therefore, we can rewrite the expression:
[tex]\frac{2^{\frac{1}{2} }}{2^{\frac{1}{3} }}[/tex]
Now, to write them as one power of two, we can use the quotient rule which states, [tex]\frac{x^m}{x^n} = x^{m-n}[/tex]:
[tex]2^{\frac{1}{2} -\frac{1}{3}}[/tex]
We just need to subtract 1/3 from 1/2 to get:
[tex]2^{\frac{1}{6} }[/tex]
This is the same as the 6th root of 2, which is the second option.
Leonardo has 140 in his bank account. He also gets an additional $15 each hour Write an equation to represent how much money, y, is in his account after x, hours.
Answer:
.y= 140 + 15x
Happy to help :)
I am leaning pre-cal right now and I don't understand it. I did arctan (3/-5) but got it wrong, how do you do this?
9514 1404 393
Answer:
149.04°
Step-by-step explanation:
You must consider the signs of the components of the vector. The value -5+3i will be in the 2nd quadrant of the complex plane.
When you use the single-argument arctan function, it will tell you the angle is -30.96°, a 4th-quadrant angle. (arctan( ) is only capable of giving you 1st- or 4th-quadrant angles.)
You find the 2nd-quadrant angle by adding 180° to this value:
-30.96° +180° = 149.04° = arg(-5+3i)
__
The attachments show the calculation using a suitable calculator (1st) and a spreadsheet (2nd). The spreadsheet function ATAN2(x,y) gives the 4-quadrant angle in radians, considering the signs of the two arguments. Here, we converted it to degrees. The calculator can be set to either degrees or radians.
pls answer quickly i need it
of the 400 members in a health club, 270 use the weight room, 180 use the pool and 80 use both. Determine the number of members that do not use either the weight room
or the pool.
A 30
B) 130
C 190
D) 100
I need help with this can someone help me please!!! I will give brainlist, no links!!
Leo is visiting New York City to see the Empire State building. He knows that the Empire State building is 1,484 feet tall. When he spots it, he stops and has to look up at an angle of 84.7 degrees to see the top. How far away from the base of the Empire State building is he?
Answer:
Leo stop at 1339. 3 feet tall and Leo almost reach the top of the building
force=1500 N pressure=6000 find the area contac
Answer:
[tex]Area = 0.25 \ m^2[/tex]
Step-by-step explanation:
Force = 1500N , Pressure = 6000
[tex]Pressure = \frac{Force}{Area }[/tex]
[tex]6000 = \frac{1500}{Area }[/tex]
[tex]6000 \times Area = 1500\\\\Area = \frac{1500}{6000} \\\\Area = \frac{1}{4} = 0.25 \ m^2[/tex]
What restrictions may be necessary to the domain and range of linear equations?
Answer:
There may be restrictions on the domain and range. The restrictions partly depend on the type of function. In this topic, all functions will be restricted to real number values. That is, only real numbers can be used in the domain, and only real numbers can be in the range.Q 18. Find the volume of a cylinder of diameter = 4 mm & height = 8 mm. Round to the nearest tenth if necessary. *
A. V= 131.1 mm^3
B. V= 116.9 mm^3
C. V= 100.5 mm^3
D. V= 230.0 mm^3
Answer: 100.5
Step-by-step explanation:
multiply 3.14 by 2 to the 2nd power by 8. so first 2 to the second power is 4. Then 4x8 is 32. Final step is to multiply 3.14 by 32 to get 100.48. Then you gotta round to get 100.5.
Every round in a competition costs 30 diamonds and you get 10 shards. How many diamonds will it cost you to reach 1,024 shards?
Answer:
3,090 diamonds
Step-by-step explanation:
To get 10 shards, you need to spend 30 diamonds.
First thing we need to find, how many rounds you need to play to get 1,024 shards if in each round you win 10 shards?
1,024/10 = 102,4
But you can not play 102.4 rounds, you only can play whole numbers, so we need to round it to the next whole number (not the previous one, because in that case, we would get less than 1,024 shards)
Then you need to play 103 rounds.
And each round costs 30 diamonds, then the total number of diamonds that you need is:
103*30 diamonds = 3,090 diamonds
Why anything divided by 0 go undefiened
Answer:
First, remember that mathematics is a logical construct.
So, when something has no logical sense, it is undefined.
Now, let's think about a division by zero:
If you have $100, and you want to divide it between 0 people, how much gets each one of them?.
Naturally, there is no logical answer to this question, we can not know how much gets each one of these people because we have no people to divide that money.
Now, we can find another logical problem if we assume that the division is actually defined.
For example if 1 divided by zero is equal to a number A, we have:
1/0 = A
ok, if now multiply both sides by zero we get:
(1/0)*0 = A*0
1*(0/0) = A*0
1 = 0
So, 1/0 can be defined only if 1 = 0, again, a logical problem.
This is why the division by zero is not defined.
Find the value of x. PLEASE HELP ASAP!!!!!!
Answer:
I don't want to be silly here, but....
if x > 9 and < 13...
there is only one answer that is >9 and < 13
that is answer "A" (11)
Step-by-step explanation:
Answer:
A. 11
Step-by-step explanation:
Hi there!
We're given the trapezoid EBFD, with bases (the parallel sides) EB and DF, which equal 9 and 13 respectively
AC is a segment that belongs to EBFD, and has the measure of x
AC is a midsegment, which is a segment that connects the midpoints of 2 sides
the midpoint divides a segment to create create two congruent segments
In this example, point A is a midpoint, as it divides ED into the congruent segments EA and AD (you can tell they are congruent by their markings)
C is also a midpoint, as it divides BF into the congruent segments BC and CF
line segment AC connects the points A and C together
anyway, the measure of a midsegment in a trapezoid is the average of the bases
in other words, the midsegment (AC, or x) is equal to (EB+DF)/2
since we know the measures of EB and DF, we can substitute them into the expression above to find x
x=(EB+DF)/2
x=(9+13)/2
add the numbers on the numerator
x=22/2
divide
x=11
So the answer is A
Hope this helps! :)
HELP ASAP !!!! Which equation is satisfied by all three of the plotted points?
Answer:
Ok, so im not 100% sure about this answer but i think its D:
Step-by-step explanation:
I think this is correct because i used desmos and had plotted those answer and the only one that looks close enough to this answer was D.
I'll also put up the pictures so you can see what i mean.
I hope this help.
f(x)=1/x−4−6f(x)= x−41 −6. Find the inverse of f(x) and its domain.
Answer:
C
Step-by-step explanation:
Given f(x) then f(x + a) is a horizontal translation of f(x)
• If a > 0 then a shift left of a units
• If a < 0 then a shift right of a units
The graph of g(x) is the graph of f(x) shifted 6 units left , then
g(x) = f(x + 6) → C
Which number is a rational number?
Answer:
C
Step-by-step explanation:
17.156 is the irrational number as it is terminating(means it ends)
Rest all are irrational
Claris invested $140. She earned a simple interest of 3% per year on the initial investment. If no money was added or removed from the investment, what was the amount of interest Claris received at the end of two years? Show all work. Calculator allowed
Answer:
$8.40
Step-by-step explanation:
The formula for calculating simple interest is
principal * interest rate * time .
Plugging 140 into the principal, or starting value, 3% as the interest rate, and 2 (years) for the time, we get 140*0.03*2 = 8.4, or $8.40 as our answer. Note that 3% turned into 0.03 as turning a percentage into a decimal requires us to divide the decimal by 100
Help me please which expression is equal
The answer is C.
45^-3 can be transferred to the denominator, making the 45 in the denominator have a power to the 6th power.
Luke's tyre pressure gauge shows a reading which is 8% higher than the actual pressure.
What is the actual pressure when Sue's gauge shows 39.42?
Answer:
so for this we do
39.42*1.08=42.5736
Hope This Helps!!!
the quotient of 4 divided by 7 is a decimal number. how many digits in the quotient are overlined?
Answer:
6 digits.
Step-by-step explanation:
The repeating numbers after the decimal is 571428.
Please help and thank you!
Answer:
f(x) = 4*e^(0.05*x)
Step-by-step explanation:
We want to find the equation for the graph.
The first thing we can see, is that, as the value of x increases, also does the value of y.
So f(x) increases as x increases.
Then we can discard the options with negative exponents, as those decrease when x increases.
Then the remaining options are:
f(x) = 4*e^(0.05*x)
f(x) = 4*e^(0.5*x)
In the graph, we can see that:
f(5) ≈ 5
So let's check that with the two remaining options:
For the first one we have:
f(5) = 4*e^(0.05*5) = 5.13
While for the second option we have:
f(5) = 4*e^(0.5*5) = 48.73
Then the correct option is the first one:
f(x) = 4*e^(0.05*x)
a man bought 250 electric lanterns in the united States of America for $5000. he sold them them in lagos at 1,920 naira each. at the time of his journey back to USA, the exchange rate was #96 to dollar
1. if selling at the lanterns at 1920 naira each, he made a profit of 20% cal the exchange rate the time he bought the lantern
2. how much in dollar will the sales amount to the of his journey back to USA
Answer: 4166.67$
Step-by-step explanation:
1920 x 250 = amount
Amount = 120%
Cost price = 100%
1920 x 250= 120%
Cost price = 100%
Cross multiply and divide both side by 120
1920 x 250 x 100/120 = price
Exchange rate = cost in #/cost in $
= (1920 x 250 x 5/6)/(5000)
= (96 x 5/6) = 16 x 5= 80
Exchange rate then was 80 to 1$
The sales will be 400000/96 = 4166.67$
Answer:
1. $1:#80
2.$5000
Step-by-step explanation:
ok... lots of moving parts here ....
$5000 / 250 = $20 per lantern.
~~~~~~~~~~~~~~~~~~
x (1 + .2) = 1920
x = 1600
~~~~~~~~~~~~~~
$5000 : (1600*250)
$5,000:#400,000
c
~~~~~~~~~~~
sales back to the us at $1:#96
1920*250 = 480000
#480000/#96=$5000
If k(x) = 5x - 6, which expression is equivalent to (k + k)(4)?
Answer:
52
Step-by-step explanation:
k(x) = 5x - 6
(k + k)(4) =
First find k(4) = 5(4)+6 = 20+6 = 26
(k + k)(4) = 26+26 = 52
Kofi, Kojo and Ama shared GH¢ 480,000.00 in the ratio 3:5:4. How much did Ama receive?
A. GH¢ 160,000.00
B. GH¢ 200,000.00
C. GH¢ 218,181.81
D. GH¢ 342,859.14
Answer:
160000
Step-by-step explanation:
Let ratio be 3x,5x,4x
Sum of ratios 3x+5x+4x=12x
Share of Kofi:-
(3/12)x480000=120000
Share of Kojo:-
(5/12)x480000=200000
Share of Ama:-
(4/12)x480000=160000
The square below is the image of a square that was dilated by a scale factor of 1. Find
the area of the preimage, the original square, before its dilation. Figures are not
necessarily drawn to scale.
11
Answer:
1,936 square units
Step-by-step explanation:
From the question, we have it that the original image was dilated by a factor of 1/4
what this mean is that the original image was reduced by up to a quarter size to get this new image
Now, to get the original image, we have to enlarge by a factor of 4
So, we simply have to multiply the side length of the new square by 4
We have that as;
11 * 4 = 44 units
Mathematically, the area of a square is the square of its side length
So, we have the area of the square as;
44 * 44 = 1,936 square units
Eliza says, “Every member of the population is equally likely to be selected for the sample”. Which type of sample is Eliza describing?
a
a random sample
b
a biased sample
c
a stratified sample
d
a quota sample
Answer: A. A random sample
Step-by-step explanation:
Since everyone is equally as likely yo be selected for this sample, is has to be random because there won't be any interference to the probability of your chances of being selected in the population
I hope this helps!
2. Mr. Theorem writes the expression 6^2/(2m) on the board. What is the value of this expression when the value of m = 3?
Answer:
6
Step-by-step explanation:
6^2/(2m)
Let m = 3
6^2/(2*3)
6^2 / 6
36/6
6
Answer:
6
Step-by-step explanation:
(6)² / 2m
36 / 2 × (3 ) ( given :- m = 3)
36 / 6
6