The Official Homework Help Thread

[Dawnpiplup]

no that graph is not a y function because it has an infinite number of y values
that also isn't even a y= line its actually an x= line which is not a function

- - - Post Merge - - -

and yes what you said was correct

- - - Post Merge - - -

the line is x=2 to be exact

Ah ok, so I understand what you said about it not being a function because of the infinite number of y values...but I don't really understand about the thing about the y= line and x=line though

- - - Post Merge - - -

A function is an expression that has 1 output for every input.

Let's keep this in mind as we go over your homework:

{(3, -8), (3, 2), (6, -1), (2, 2)}

You said: "No, because 3 is paired with 2 range values.", which is 100% correct. Good job.

"Also, the problem above had two "2"s in the Y place."

This is okay. This is two similar outputs, but you get them from different inputs. In each case, your input of 3x = 2y, and your input of 2x = 2y has a different input.


As for the graph, there's a test you can do to tell if it's a function at a glance. Place your pencil vertically on the paper, and if it touches 2 or more spots on the graph, it's not a function. (Because that would mean it has 2 or more outputs for a single input)

Oh ok, I think I get it now thanks guys!

 

[JellyLu]

Does anyone know how to deal with obtaining genotype frequencies by looking at an allozyme gel?
I have to do this but the gel I'm looking at doesn't have any labels, it just has the lines ;;

 

[Llust]

im working on this machine for my project, and what's primarily required is various types of energy transfers as well as a minimum of thirty steps, but my main concern is how to use each energy transfer. the only transfers i have left are radiant, heat, electric and nuclear. i have no idea how to involve those three in my machine without something going wrong, so i'd appreciate some ideas on what i could do to perform them

for radiant, i'll be using magnets. the magnets im using are really strong, so that has some advantages and disadvantages alone. i just don't know how to use them to keep the flow of the machine going and how to trigger it. so far, what i have in mind is just tying the magnets on both ends of a string. as for electric and nuclear, im clueless

 

[That Zephyr Guy]

Could somebody who knows how to solve a differential equation double check this answer for me?


A body was found at 8AM measuring at 80 degrees F. An hour later it was measured to be 78.5 degrees. The room it was found in has been a constant 68 degrees all week. At what time did the person die? Their normal body temperature was known to be 96 degrees.

Spoiler: This is my work so far

Me and a few classmates corroborated to get similar results which don't match anything sort of what we were supposed to, so maybe somebody who's already taken this course can verify? At this point we kind of think the teacher screwed up the possible answers we could have gotten. (The expected answer is somewhere after at least 2 AM apparently.)

 

[KarlaKGB]

Could somebody who knows how to solve a differential equation double check this answer for me?


A body was found at 8AM measuring at 80 degrees F. An hour later it was measured to be 78.5 degrees. The room it was found in has been a constant 68 degrees all week. At what time did the person die? Their normal body temperature was known to be 96 degrees.

Spoiler: This is my work so far

Me and a few classmates corroborated to get similar results which don't match anything sort of what we were supposed to, so maybe somebody who's already taken this course can verify? At this point we kind of think the teacher screwed up the possible answers we could have gotten. (The expected answer is somewhere after at least 2 AM apparently.)

Spoiler

i get the same answer as u

 

[That Zephyr Guy]

Spoiler

i get the same answer as u

Aight, the teacher got the times wrong then. Rip.

Thanks

 

[KarlaKGB]

i mean it's possible we all made a really easy mistake but idk, looks like ur teacher messed up

 

[Dawnpiplup]

I need help with my Math homework again...Can someone explain how to do this problem? It says:

Find the rate of change (slope) of each line.

0=-4y+8+x

 

[Artist]

I need help with my Math homework again...Can someone explain how to do this problem? It says:

Find the rate of change (slope) of each line.

0=-4y+8+x

The equation y = mx + b says that m is the slope.
So you want to reorder your equation to make it similar to that.

0=-4y+8+x

Add 4y to both sides.

4y = 8 + x

Divide everything by 4.

y = 2 + (1/4)x

Reorder to match the y = mx + b.

y = (1/4)x + 2


So the rate of change is 1/4.

 

[Dawnpiplup]

The equation y = mx + b says that m is the slope.
So you want to reorder your equation to make it similar to that.

0=-4y+8+x

Add 4y to both sides.

4y = 8 + x

Divide everything by 4.

y = 2 + (1/4)x

Reorder to match the y = mx + b.

y = (1/4)x + 2


So the rate of change is 1/4.

Thank you so much

 

[otomatoe]

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[EpicGamer12]

for all x that belong to the set of integers, x being an odd integer implies there exists a k such that x^4 = 2k + 1

basically need help with a proof that shows that an odd integer's 4th power will always be odd

 

[Artist]

basically need help with a proof that shows that an odd integer's 4th power will always be odd

I am not sure if you are looking for a real complex way of solving this, but I guess the simplified version would be because

odd x odd = odd
so
odd^2 x odd^2 = odd

Reason: Multiplication of odd integers


Long way

Let q and r be odd integers, then q=2k+1 and r=2m+1

q?r=(2k+1)(2m+1)⟹q?r=4mk+2k+2m+1⟹q?r=2(2mk+k+m)+1

It would then conclude that q?r results in an odd number, because 2 times an integer with one added to it is, by definition, an odd number.


In your case, you would only need to use 1 variable q which = 2k+1

so q^2 = (2k + 1)(2k +1) = 4k^2 + 4k + 1

q^4 = (4k^2 + 4k + 1 )(4k^2 + 4k + 1 ) = 16k^4 + 16k^3 + 4k^2 + 16k^3 + 16k^2 + 4k + 4k^2 + 4k + 1
q^4 = 16k^4 + 32k^3 + 24k^2 + 8k + 1

q^4 = 2(8k^4 + 16k^3 + 24k^2 + 4k) + 1

Therefore it results in an odd number because any integer multiplied by 2 and added by 1 is by definition an odd number.

someone check my math tho i just did this on the fly

 

[EpicGamer12]

I am not sure if you are looking for a real complex way of solving this, but I guess the simplified version would be because

odd x odd = odd
so
odd^2 x odd^2 = odd

It's a lot more complex than that but thanks haha

 

[teshima]

Can someone explain to me how and when lequel and its variations are used in french?

 

[Artist]

I am not sure if you are looking for a real complex way of solving this, but I guess the simplified version would be because

odd x odd = odd
so
odd^2 x odd^2 = odd

Reason: Multiplication of odd integers


Long way

Let q and r be odd integers, then q=2k+1 and r=2m+1

q?r=(2k+1)(2m+1)⟹q?r=4mk+2k+2m+1⟹q?r=2(2mk+k+m)+1

It would then conclude that q?r results in an odd number, because 2 times an integer with one added to it is, by definition, an odd number.


In your case, you would only need to use 1 variable q which = 2k+1

so q^2 = (2k + 1)(2k +1) = 4k^2 + 4k + 1

q^4 = (4k^2 + 4k + 1 )(4k^2 + 4k + 1 ) = 16k^4 + 16k^3 + 4k^2 + 16k^3 + 16k^2 + 4k + 4k^2 + 4k + 1
q^4 = 16k^4 + 32k^3 + 24k^2 + 8k + 1

q^4 = 2(8k^4 + 16k^3 + 24k^2 + 4k) + 1

Therefore it results in an odd number because any integer multiplied by 2 and added by 1 is by definition an odd number.

someone check my math tho i just did this on the fly

It's a lot more complex than that but thanks haha

sorry i was editing my post lol
but if i still got it wrong then i interpreted ur post wrong
good luck

 

[EpicGamer12]

sorry i was editing my post lol
but if i still got it wrong then i interpreted ur post wrong
good luck

yeah, I figured it out and it's pretty close to what you had, so props.
I am now struggling with "prove x^2 - y^2 is composite for any two integers x, y such that x > y > 5 and x - 5 > y"

 

[Dawnpiplup]

Did I do this math problem right?

The math problem is: 5x-8y=16

I solved the math problem like this:

5x-8y=16
I subtracted 5x on the left side, and added -5x on the right side. This gave me -8y=16-5x.
----------------
-8y=16-5x
/-8 /-8 /-8
----------------
y=-2+5/8x

I then switched the numbers around to make it look like y=mx+b, so my final answer was y=5/8x-2. Was this right?

Also, can someone explain how to do math problem #25 to me?

Spoiler: Picture of math problem

 

[That Zephyr Guy]

Did I do this math problem right?

The math problem is: 5x-8y=16

I solved the math problem like this:

5x-8y=16
I subtracted 5x on the left side, and added -5x on the right side. This gave me -8y=16-5x.
----------------
-8y=16-5x
/-8 /-8 /-8
----------------
y=-2+5/8x

I then switched the numbers around to make it look like y=mx+b, so my final answer was y=5/8x-2. Was this right?

Also, can someone explain how to do math problem #25 to me?

Spoiler: Picture of math problem

You did it totally right, good job.


To do number three, remember that slope is rise over run, or movement in the Y direction for every movement in the X direction. The slope here is 3/2, which means you move up 3 y coordinates for every 2 x coordinates. The y intercept is -5, so it means that the line intersects the y axis at -5.

 

[Dawnpiplup]

You did it totally right, good job.


To do number three, remember that slope is rise over run, or movement in the Y direction for every movement in the X direction. The slope here is 3/2, which means you move up 3 y coordinates for every 2 x coordinates. The y intercept is -5, so it means that the line intersects the y axis at -5.

Thanks