Question

Sketch the directional field

Answer 1

that's a tricky one. we could treat the function as a constant or just plug in whatever values of x and y. if it's positive, it's a tan 45 slant.. negative? - tan 45 slant

Answer 2

why treat the function as a constant?, how do we know if it is positive or negative? sry im still blur about this topic..

Answer 3

what my prof did last semester was change the y prime to C = 1-xy and let C = 0... then you find all x and y values that equal whatever C was which in this example is 0.

Answer 4

my prof thinks it's faster... true...but I use the other method as a backup

Answer 5

how do u know C is 0? isit because of the (0,0)? --> what does this mean? an interval or x,y axis? i dont understand my pof thts why im here T^T

Answer 6

@LastDayWork

Answer 7

sorry I just went through a rough time with my assignment... argh that was in my face... x(

Answer 8

now to drunk latex this thing before I go bed

Answer 9

@UsukiDoll haha its okay u shd go rest thanks anyways(:

Answer 10

Hey, do you know how to solve "first order linear differential equations" ?

Of type -
y' + Py = Q

where P and Q are functions of x

Answer 11

that's linear..........

Answer 12

oh gawd Ineed sleep...I mgdsfa;jfkl bubbble brain out like my assignment...

Answer 13

i think i know but i have forgotten, i think i alr know how to solve this but so long winded, since need to plot lots of points is there another way to find the solution at that point? haha i think im asking too much :p

Answer 14

slope fields suck. it's either the long plug and play way or the constant version.

Answer 15

@ememlove
Can you rephrase what you just said ?

Answer 16

ok going to bed I might fall asleep on teh screen night guys

Answer 17

Gud nite @UsukiDoll

Answer 18

haha, okay nvm, i guess i still have to plot the directional field one by one right? then find the solution curve at(0,0) night @UsukiDoll

Answer 19

zzzzzzzzzzzzzzz

Answer 20

Well the general solution is -
\[y*e ^{\int\limits P dx}=\int\limits Q*e^{\int\limits P dx} dx + C\]

I hope you can see the equation.

Answer 21

Next you can substitute (0,0) for x and y to get C.

Answer 22

i cant see the equation >< sry!

Answer 23

To fix the problem; visit -
http://openstudy.com/study#/updates/52de57e0e4b003c643a10b24

Answer 24

^^ @ememlove

Answer 25

okay thanks! (: after i find C then?

Answer 26

Then, the equation you'll get would be the solution curve.

Answer 27

i see, okay thanks alot! that helps so muccchhh!! :D

Answer 28

:)