My brain has died, please help.

How can you rearrange a = f / (f-n) to make f the subject?

(For those who are wondering why, I'm trying to extract the near and far clip planes from a projection matrix)

Quote from Crashgate3 :

My brain has died, please help.

How can you rearrange a = f / (f-n) to make f the subject?

(For those who are wondering why, I'm trying to extract the near and far clip planes from a projection matrix)

probably wrong but i got it to af-an = f

That's not making f the subject. All the f's need to be on one side.

Quote from Crashgate3 :

That's not making f the subject. All the f's need to be on one side.

thought so, my maths went only as far as gcse, ill stick to my biology

I got as far as f - f = an/a :|

Got it (I think)

f = -n / (1/a - 1)

Is my working correct?

Quote :

a = f / (f-n)

(divide both sides by f)

a / f = 1 / (f - n)

(turn upside down)

f / a = f - n

-f / a = n - f

-f / a + f = n

-f * 1/a + f = n

(factor f out of the left hand side)

-f (1/a - 1) = n

-f = n / (1/a - 1)

EDIT: Yeah, seems to work.

a = f / (f-n)
a(f-n)=f
af-an=f
af-f=an
f(a-1)=an
f=an/(a-1)

a = f / (f-n)
a(f-n)=f
af-an=f
af-f=an
f(a-1)=an
f=an/(a-1)

Get what you think is the formula, find f and insert it into the original formula to see if it all adds up.

f = fffffffffffuuuuuuuu

Quote from Gills4life :

f = fffffffffffuuuuuuuu

fffffffffffuuuuuuuu = (f^11)(f^8)

Wrong!

Quote from Gills4life :

f = fffffffffffuuuuuuuu

f=0

I HATE MATHS. I made it nice and simple and then people had to start complicating things.

Quote from RasmusL :

f=0

or u=1 and f=1

Quote from amp88 :

Help?

That's amazing! Can it do any formula?

It can answer anything, not only math problems... Type practically any question and it will answer.