Algebra

[Daolas]

Hey all,

It's been sometime (20 years) since I was in college... can anybody factor out the attached equation.... .I need to find out what "F" is equal to.

Thanks in advance

Dao

http://i74.photobucket.com/albums/i273/berdar/Untitled.jpg

 

[gigaheadman]

if your asterixes mean 'times', then i get it to be;

F = ( pi * d^2 ) / ( 2p * 2w)

 

[amy711]

I actually got
(pi*d2)/(p2*w2)= F

 

[ChrisPharmD]

Hmmm... I got F = (2d^2)/(pi^2*w^2)

*That's assuming the II is a 2.

 

[kmb411]

I matched Amy's answer

 

[ChrisPharmD]

I just realized that the II is pi. Sorry, I was thinking you meant the 'p' to be pi.

 

[ReadyOne]

Hey all,

It's been sometime (20 years) since I was in college... can anybody factor out the attached equation.... .I need to find out what "F" is equal to.

Thanks in advance

Dao

http://i74.photobucket.com/albums/i273/berdar/Untitled.jpg

I'm sure this has been overcome by events, but...

First, a note on written algebraic notation. When you see a constant used as a multiplier, it precedes the variable, e.g. 2x means "2 times x".

Since we read p2 and w2, it is inconsistent for the "2" to be a constant multiplier.

This gives us two options. "p2" is actually p superscript 2, meaning p squared. But given the quality of formatting done as a graphic with the square root symbol, it's probable that the 2 would truly be in a superscript position if squaring were intended.

The remain option is a hybrid notation where p2 and w2 are variable names from a programming language type notation, and each represents just a single quantity. Support for this is added by the common programming language notation of using star "*" to indicate multiplication.

Finally, close inspection of the "II" reveals that the top is connected but the bottom is not, in the style of the capital Greek letter pi. This symbol is used in statistics and often found in equations involving squares and square roots, and does not represent the constant 3.1415926... (normally denoted with the lower case Greek pi).

I'll use II below instead of the true Greek capital pi. Also, d^2 means "d squared", which is another programming language notation convention.


Now for the algebra. Remember the basic rule is: do the same unto both sides of the equal sign.

1. Get rid of the square root by squaring both sides:

d^2 = (p2 * w2 * F) / II

2. Get rid of the fraction by multiplying by II.

(d^2) * II = (p2 * w2 * F)

3. Cancel out p2 and w2 by dividing by (p2 * w2)

(d^2) * II / (p2 * w2) = F


Or if you want to go slower....

3a. Add parens to the left side for clarity.

( (d^2) * II) = (p2 * w2 * F)

3b. Since the right hand side is all terms multiplied together, they may be reordered and parens can be removed.

( (d^2) * II) = F * p2 * w2

3c. Divide both sides by w2, which is the same as multiplying by 1/w2.

( (d^2) * II) * 1/w2 = F * p2 * w2 * 1/w2

The w2 cancels out of the right hand side leaving

( (d^2) * II) * 1/w2 = F * p2 * (w2 * 1/w2)
( (d^2) * II) * 1/w2 = F * p2 * (1)
( (d^2) * II) * 1/w2 = F * p2

3d. Same trick removes p2 from the right hand side

( (d^2) * II) * 1/w2 * 1/p2 = F

3e. Flip sides for convenience:

F = ( (d^2) * II) * 1/w2 * 1/p2

3f. Consolidate the right hand side. Remember division and multiplication are the same kind of operation, so parens can be added or removed around any terms being multiplied or divided together.

F = ( (d^2) * II) * (1/w2) * (1/p2)
F = ( (d^2) * II) * (1/w2 * 1/p2)
F = ( (d^2) * II) * (1 / (w2 * p2) )
F = ( (d^2) * II) * 1 / (w2 * p2)

3g. Multiplying something by 1 is superfluous and can be removed.
F = ( (d^2) * II) * 1 / (w2 * p2)
F = ( ( (d^2) * II) * 1) / (w2 * p2)
F = ( (d^2) * II) / (w2 * p2)

3h. As can the extra set of parens introduced in 3a.
F = (d^2) * II / (w2 * p2)

 

[mediocre]

OW! My head hurts.

(I know you are being helpful, I'm just being a smart ass. I haven't done algebra for a very long time)

 

[youngleo]

What the hell

 

[paradox_inversion]

This thread hurts my brain.

 

[NippleMuncher]

Damn it with the theoretical numbers!



I've never been able to wrap my brain around algebra.

 

[HornyHenry]

Algae Bra?

Isn't that what mermaids wear?
Great explaination, ReadyOne.

 

[CheekyGiRL07]

OK, I am now going to Lit. for homework help.