Integration (1 Viewer)

[yeyjasminetime]

Hi,

Find y as a function of x, if y' = 1/4x and y= 1 and y = 1 when x = e². What is the x intercept of this curve?

If someone could explain this to me, it would be great. Thank you.

 

[AnimeX]

Hi,

Find y as a function of x, if y' = 1/4x and y= 1 and y = 1 when x = e². What is the x intercept of this curve?

If someone could explain this to me, it would be great. Thank you.

is that a typo?

 

[yeyjasminetime]

Yes, just y= 1 once

 

[SharkeyBoy]

y' = 1/4 x
y = 1/8 x^2 + c
1 = 1/8 e^4 + c
c = 1 - 1/8 e^4
therefore:
y = 1/8 x^2 - 1/8 e^4
to find x int, sub y =0
therefore x = plus/minus e^2

 

[HeroicPandas]

mistake...

 

[D94]

"y' = 1/4 x
y = 1/8 x^2 + c"

Thats differentiation, if u differentiate y' (dy/dx) with respect to x, then u get y'' (d^2 y/dx^2), not y

It's because SharkeyBoy interpreted the integrand as (1/4)x, whereas you interpreted it as 1/(4x). You are both correct, given your assumptions.

Also, this was the first of two identical threads created.

 

[HeroicPandas]

It's because SharkeyBoy interpreted the integrand as (1/4)x, whereas you interpreted it as 1/(4x). You are both correct, given your assumptions.

Also, this was the first of two identical threads created.

oh right lol (and it he didnt differentiate aswell lol...)