For any two numbers a and b, the product of a − b times itself is equal to a^2 − 2ab + b^2. Does this familiar algebraic result hold for dot products of a vector u − v with itself? In other words, is it true that (u − v) • (u − v) = u • u − 2u • v + v • v? Justify your conclusion, trying not to express vectors u and v in component form.
Answers
Answer:
yes; the distributive property applies to dot products
Step-by-step explanation:
The product of (a-b) with itself is ...
(a -b)·(a -b) = a² -2ab +b²
because the commutative and distributive properties apply to multiplication.
(a -b)·(a -b) = a(a -b) -b(a -b) = a² -ab -ba +b² = a² -ab -ab +b² = a² -2ab +b²
__
The same expansion works for the dot product operation, because the commutative and distributive properties hold for that operation, as well.
(u −v)•(u −v) = u•(u -v) -v•(u -v) = u•u -u•v -v•u +v•v
= u•u -u•v -u•v +v•v = u•u -(u+u)•v +v•v = u•u -2u•v +v•v
_____
Additional comment
The proof of any of the properties of the dot product relies on expressing the vectors in component form. The distributive property is no exception.
Related Questions
There are 36 boys for every 54 girls
Answers
Answer:
2 : 3 is ur ratio
Step-by-step explanation:
Answer:
2 : 3 is ur ratio
Step-by-step explanation:
Write an expression that is equivalent to 4(x + 1) - 7 (x + 3)
Answers
Answer:
-3x-17
Step-by-step explanation:
We need to expand this term by multiplying a term and an expression.
The following product distributive property will be used:
.
In our example, the resulting expression will consist of 2 terms:
the first term is a product of and .
the second term is a product of and .
Therefore, one expression that is equivalent to 4(x + 1) - 7(x + 3) is -3x - 17.
Hoped this helped.
[tex]-BrainiacUser1357-[/tex]
X=-2y,x-y=6 solve by substitution show all work
Answers
Answer:
y=-3
x=3
Step-by-step explanation:
x=-2y
x-y=9
substitute -2y for x in the second equation
you get:
-2y-y=9
combine like terms
-3y=9
divide by -3 on both sides
y=-3
write one in factor form with solutions 3,-1,-3i?
Answers
Answer:
Factored form: [tex](x-3)(x+1)(x^2+9)[/tex]
Expanded form: [tex]x^4-2x^3+6x^2-18x-27[/tex]
Step-by-step explanation:
[tex](x-3)(x+1)(x^2+9)[/tex]
[tex](x^2-2x-3)(x^2+9)[/tex]
[tex]x^4+9x^2-2x^3-18x-3x^2-27[/tex]
[tex]x^4-2x^3+6x^2-18x-27[/tex]
[tex]x-3=0[/tex] has a solution of [tex]x=3[/tex]
[tex]x+1=0[/tex] has a solution of [tex]x=-1[/tex]
[tex]x^2+9=0[/tex] has a solution of [tex]x=\pm 3i[/tex]
Jenna has 38 coins. She uses 19 coins to buy a notebook. How many coins does she have left?
Explain how you can solve and check this problem.
Answers
Answer: 19 coins
Step-by-step explanation:
38-19=19
To check, take any one of the nubers and replace it with x, and when you solve for x. you'll get that number back. For example:
Let x represent the amount used to buy a notebook
19+x=38
x=38-19
x=19
You solve the problem by subtracting how many coins she used by how many coins she has
DOM
The weight of a car is modeled with the polynomial 3x2 – 25x + 204. The weight of a truck is modeled with the polynomial x² + 17x + 40
What polynomial represents the total weight of the car and truck?
Answers
Answer:
4x^2-8x+244
Step-by-step explanation:
Anna saved $20 in a jar each month for 2 1/2
years. She spent 75% of her savings on a computer. How much money did Anna have left in the jar?
Answers
Answer:
20*2.5=50
50*0.75=37.5
Hope This Helps!!!
Answer:270
Step-by-step explanation:
Brody worked 8.5 hours at Food Lion this week and made $78.20. Based on the number of hours Brody worked and how much he was paid, how much money does Brody make per hour
Answers
Answer:
1 hour = $9.2
Step-by-step explanation:
The question says that:
Brody makes $78.20 in 8.5 hours.
So,
8.5 hours = $78.20
We need to find 1 hour pay.
So, divide both sides of the above equation by 8.5
8.5 / 8.5 hours = $78.20 / 8.5
1 hour = $9.2
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807Consider a parallelogram with vertices at (0, 3), (2, 0), (4, 2), and (2, 5).
2) Suppose the parallelogram is reflected over the x-axis, which vertex of the parallelogram will have the same coordinate before and after the reflection?
A) (0, 3)
B) (2, 0)
C) (2, 5)
D) (4, 2)
Answers
Answer:
B
Step-by-step explanation:
So a reflection over the x is a change in the y value.
Only point (2,0) is on the x-axis, so it will not move.
7m 28cm ÷8= something cm
Answers
Answer:
4cm
Step-by-step explanation:
it this the answer you were looking for?
Answer:
91cm
Step-by-step explanation:
7m to cm =700m
28cm+700cm=728cm
728cm/8=91cm
I need help on this question
3n + 2 = 17
Answers
Answer:
The value of n is 5.
Step-by-step explanation:
Concept :
Here, we will use the below following steps to find a solution using the transposition method:
Step 1 :- we will Identify the variables and constants in the given simple equation.Step 2 :- then we Simplify the equation in LHS and RHS.Step 3 :- Transpose or shift the term on the other side to solve the equation further simplest.Step 4 :- Simplify the equation using arithmetic operation as required that is mentioned in rule 1 or rule 2 of linear equations.Step 5 :- Then the result will be the solution for the given linear equation.Solution :
By using the transposition method. we get,
[tex]{\dashrightarrow{\tt{3n + 2 = 17}}}[/tex]
[tex]{\dashrightarrow{\tt{3n= 17 - 2}}}[/tex]
[tex]{\dashrightarrow{\tt{3n= 15}}}[/tex]
[tex]{\dashrightarrow{\tt{n= 15 \div 3}}}[/tex]
[tex]{\dashrightarrow{\tt{n= \dfrac{15}{3}}}}[/tex]
[tex]{\dashrightarrow{\tt{n= \cancel{\dfrac{15}{3}}}}}[/tex]
[tex]{\dashrightarrow{\underline{\boxed{\tt{\red{n= 5}}}}}}[/tex]
Hence, the value of n is 5.
[tex]\rule{300}{1.5}[/tex]
Solve : 3n + 2 = 17
Answer:-n = 5
Explanation:-=> 3n + 2 = 17
=> 3n = 17-2
=> 3n = 15
=> n = 15/3
=> n = 5
Need help quickly please
Answers
Step-by-step explanation:
just want your ponit hahahaHA
how much is 3 liters in 50 bottles
Answers
Answer : 0.06 liters per bottle
Step - by - step explanation :
3 liters divided by 50 bottles = 0.06 liters per bottle
[ Sorry if this wasn't what you meant when you asked the question ]
Happy holidays ! :3
write an equation
(X-P) (x-q)=0
Answers
Answer:
[tex]x^{2} -pqx+pq[/tex]
Step-by-step explanation:
Which one of Aiko's steps makes a false assumption? Why is it false?
Aiko's Proof:
1. Draw 2 rectangles. Label one ABCD and the other PQRS
2. Translate rectangle ABCD by the directed line segment from A to P.A' and P now coincide. The points coincide because that's how we defined
our translation
3. Rotate rectangle A'B'C'D' by angle D'A'S. Segment A"D" now lies on ray PS. The rays coincide because that's how we defined our rotation.
4. Dilate rectangle A"B"C"D" using center A" and scale factor AD. Segments A"D" and PS now coincide. The segments coincide because A" was
the center of the rotation, so A" and P don't move, and since D" and S are on the same ray from A", when we dilate D" by the right scale factor, it
will stay on ray PS but be the same distance from A" as S is, so S and D' will coincide.
5. Because all angles of a rectangle are right angles, segment A'B' now lies on ray PQ. This is because the rays are on the same side of PS and
make the same angle with it (If A'B' and PQ don't coincide, reflect across PS so that the rays are on the same side of PS.)
6. Dilate rectangle A"B"C"D" using center A" and scale factor AB Segments A'"'**" and PQ not coincide by the same reasoning as in step 4.
7. Due to the symmetry of a rectangle, if 2 rectangles coincide on 2 sides, they must coincide on all sides.
Answers
Answer:
6th step is wrong
Step-by-step explanation:
We have the dilation transformations we only needed one, and that is the 6th step. It would make more sense to do the dilation transformation early in the steps and we already did these steps at the beginning.
An 18-foot ladder is leaning against a wall. The bottom of the ladder is 4.5 feet from the base of the wall.
How high up the wall does the ladder reach? Round your answer to the nearest tenth, if necessary.
A
13.5 feet
B
18.6 feet
o
С
22.5 feet
D
17.4 feet
Answers
Answer:
d
Step-by-step explanation:
use Pythagoras theorem
that is a²+b²=c²
so 4.5²+b²= 18²
rearrange to b²=18²-4.5²
so you get b=
[tex] \sqrt{303.75} [/tex]
that is equal to 17.42842506
Two cars leave an intersection at the same time. One drives east while the other travels south at 25 miles per hour faster than the other. After 2 hours, the cars are 250 miles apart. How fast is the southbound car driving?
Answers
Step-by-step explanation:
Pythagoras :
c² = a² + b²
c is the Hypotenuse (side opposite of the right angle), which is in our case the distance of the 2 cars.
after 2 hours the east car was driving x miles. and the south car was driving x + 2×25 = x + 50 miles.
x² + (x + 50)² = 250²
x² + x² + 100x + 2,500 = 62,500
2x² + 100x = 60,000
x² + 50x = 30,000
x² + 50x - 30,000 = 0
the solution for a quadratic equation is
x = (-b ± sqrt(b² - 4ac))/(2a)
in our case
a = 1
b = 50
c = -30,000
x = (-50 ± sqrt(2500 - 4×1×-30000))/(2×1) =
= (-50 ± sqrt(2500 + 120000)/2 =
= (-50 ± sqrt(122500))/2 = (-50 ± 350)/2 =
= -25 ± 175
x1 = -25 + 175 = 150 miles
x2 = -25 - 175 = -200 miles.
negative distances don't make any sense here in our scenario, so the solution is x = 150 miles.
therefore, the east car was going 75 mph (traveled in 2 hours 150 miles).
and the south car was going 75 + 25 = 100 mph (traveled in 2 hours 200 miles).
What is the end behavior of the graph of the polynomial function f(x) = 3x^6 + 30x^5 + 75x^4?
Answers
Answer:
[tex]f(x)\longrightarrow\infty[/tex] as [tex]x\longrightarrow\infty[/tex]
Step-by-step explanation:
We can see that all parts of the polynomial are positive, so as x gets larger, y will also get larger.
explain please i dont get it
Answers
Answer:
.........................
......
Here is a photo of the question it self. I hope it makes it easier to understand
Thank you for anyone who helps with the question
Answers
Answer:
a. R>S
b. It means that R is to the right of S
c. City R is warmer
Step-by-step explanation:
1 Name the shapes that are being described. a I have three sides that are all the same length. I have three equal angles. Thave three lines of symmetry and rotational symmetry of order 5. b I have four sides. Thave one line of symmetry and rotational symmetry of order 1. Two of my angles are equal. I have two pairs of equal length sides' C I have six sides. All my sides are the same length. I have six lines of symmetry and rotational symmetry of order
Answers
Answer:
a. Equilateral triangle
b. Quadrilaterals
c. Hexagon
Step-by-step explanation:
Plz help with this question.If can't do it don't answer.
Answers
Answer:
the total surface area of this triangular prism is 976cm2
Answer:
i think TSA = 976 cm²
Step-by-step explanation:
TSA = 2(1/2×14×24) + (14+25+25)×10
TSA = 2(7×24)+(64×10)
TSA = 336+640
TSA = 976 cm²
Find 85 - 72 x 4 ÷ 2 (13 - 11)
Answers
Answer:
13
Step-by-step explanation:
using BODMAS
13-11=2
SO 2*2=4
4/4=1
1*72=72
THEREFORE it is 85-72 =13
PLZ HELP
Use the distributive property to remove the parentheses.
Answers
Answer:
I don't know if i did this correctly because i can't find my notes but i hoped i helped.
Step-by-step explanation:
PLEASE HELP ASAP! I WILL GIVE BRAINLIEST JUST PLEASE HELP
Answers
Answer:
38cm squared
Step-by-step explanation:
Which type of laboratory is not required to have coved floors (where the floor runs continuous for the wall for a few inches)
Answers
The type of laboratory that is not required to have coved floors is a BSL2.
Safety in laboratories is measured through the Biosafety Level scale. This scale evaluates how much protection do people working in the laboratory need to avoid any risks while working with pathogens or toxins.
This scale goes from 1 to 4 and the 4 level represents labs in which extremely dangerous pathogens are studied, and therefore labs with the highest safety protocols.
In this context, coved floors are not required for labs classified in Biosafety level 2 because in these labs pathogens have only a moderate risk, therefore some precautions such as the coved floors are not required.
Learn more about labs in: https://brainly.com/question/14428286
Find the m, b, and write the equation for the following graph:
Answers
Answer:
y=3
Step-by-step explanation:
m=0
b=3
What is the slope of the line that passes through the points shown in the table?
X Y
-1 -5
0 -3
1 -1
2 1
Answers
Subtract: x2 + 2x + 1 – (x – 3)
Answers
Therefore, the answer is 3x - 2.
Hoped this helped.
[tex]BrainiacUser1357[/tex]
7) Sarawong spent half of his weekly allowance on candy. To earn more money his parents let him wash the dog for $6.10. What is his weekly allowance if he ended with $11.40?
Answers
Answer:
$10.60
Step-by-step explanation:
Sarawong ends with $11.40, and we need to find his weekly allowance by working backward. First, we learn that he earned $6.10 of that total amount of money by washing the dog, so we can subtract the two values:
11.4 - 6.1 = 5.3
So, before washing the dog, Sarawong had $5.30. But he only received this after spending half of his weekly allowance, so $5.30 must be half of his weekly allowance. If we multiply $5.30 by 2, we should be able to find his weekly allownce.
5.3 × 2 = 10.6
Now, we can check our work. First, he spends half of his weekly allowance on candy. Half of 10.6 is 5.3, so he now has $5.30. Then, he earns $6.10 more by washing the dog. 5.3 + 6.1 = 11.4, which is the ending value. So, our work was correct! Hopefully that's helpful. :)