Question

@Michele_Laino

Answer 1

@Loser66

Answer 2

tell me the reason why not D?

Answer 3

im not sure, how do i know if it is positive or negative?

Answer 4

@cwrw238 what do you think?

Answer 5

give me second, I need look up at the note before giving out the logic. :) I took the course long time ago. :)

Answer 6

hahah its fine(:

Answer 7

yes been a while for me too
y^2 - x^2 = c^2 is a hyperbola

Answer 8

- i remember that!

Answer 9

so i was correct? (:

Answer 10

oh wait no

Answer 11

if we differentiate 2y* dy/dx - 2x = 0

Answer 12

dy/dx = x/y

Answer 13

Nope, the d.e should be \(\dfrac{dy}{dx}=\dfrac{-x}{y}\)

Answer 14

That is the correct form of the graph.

Answer 15

http://www.ies-math.com/math/java/calc/DiffEqu/DiffEqu.html

Answer 16

yea - right

Answer 17

your graph is circles as shown, hence it can't be y^2 -x^2

Answer 18

So it would have to be positive? which would be D?

Answer 19

@cwrw238

Answer 20

yes
note that the lines have a negative slope in the first quadrant which shows that the derivative is -x/y
so it has to be a circle

Answer 21

D is correct

Answer 22

OK?

Answer 23

differentiating y^2 + x^2 = c^2 gives dy/dx = -x/y

Answer 24

I remember drawing those derivative graphs a while ago - what a pain!