Sometimes I HATE Algebra.

[Guest]

Actually, that's incorrect. The two cars end up 275 miles apart. The way you've set it up, the total distance traveled will be 275 miles (40*2.5 + 50*3.5 = 275).

It needs to be set up like this:
50(x+1) = 40x + 275
50x + 50 = 40x + 275
10x = 225
x = 22.5

Therefore, the faster car traveled (23.5 * 50 = 1175 miles) and the slower car traveled (22.5 * 40 = 900 miles) and 1175 - 900 = 275.

No no no no.....(another math geek here...sorry Muff!) seXieleXie is correct. Both cars started at the same place and went the OPPOSITE direction, one traveling EAST, the other WEST making the total number of miles for BOTH vehicles 275.

17) Two cars leave the same city at the same time. One travels west at a rate of 40 miles per hour. The other travels east at a rate of 50 miles per hour, and travels one hour longer than the slower car. If they finish 275 miles apart, what is the time of travel of the first car?

Your formula would be correct of BOTH cars were going THE SAME DIRECTION.

Moon

PS Yes Tim1, I've done hundreds of formulas for my Excell spread sheets.....then turned them into complicated graphs.....

Oh, and seXieleXie.....I'm with ya on that Matlab stuff.....hard to understand it if ya don't see any applications for it.....

 

[RawHumor]

Your formula would be correct of BOTH cars were going THE SAME DIRECTION.

DOH! Sorry, I missed that part... thanks for the clarification. I need to read posts more closely, I think (or stop trying to multitask LOL).

 

[Guest]

DOH! Sorry, I missed that part... thanks for the clarification. I need to read posts more closely, I think (or stop trying to multitask LOL).

Hehe....no problem.....I used to hate those types of problems, cause I'd have to read them over and over to make sure I got it correct.....my dad was a math and science teacher, and used to grade my homework every night, and made me do them over and over till I got them right.....yuck.

Moon

 

[Willing and Unsure]

would anyone wanna help me with my math homework? its a real bitch sometimes... i'm really beginning to hate linear algebra


10. Define a transformation T:R^2->R^2 by the following rule: T(X) is the result of first rotating X conterclockwise by pi/6 radian and then multiplying by

A = [2 0 or A = [2 3;0 3] for you matlab lovers
0 3]

a. what is the image of the circle x^2 +y^2 = 1 under T?
b. what is the image of the unit square under T?
c. find a matrix B such that T(X) = B*X for all X in R^2



*hint* R^2 is my symbol on here for all 2 dimensional space


this is one of the few problems i'm getting stuck on for my homework that's due tomorrow.. anyone care to help me some.. please?

 

[SadnonMage]

WOW! SL good looking and brains

the total package I would say.

btw weren't riff's problems more in the realm of applied physics??
Just asking..........


SM

 

[claude_moveml]

would anyone wanna help me with my math homework? its a real bitch sometimes... i'm really beginning to hate linear algebra


10. Define a transformation T:R^2->R^2 by the following rule: T(X) is the result of first rotating X conterclockwise by pi/6 radian and then multiplying by

A = [2 0
0 3]

a. what is the image of the circle x^2 +y^2 = 1 under T?
b. what is the image of the unit square under T?
c. find a matrix B such that T(X) = B*X for all X in R^2



*hint* R^2 is my symbol on here for all 2 dimensional space


this is one of the few problems i'm getting stuck on for my homework that's due tomorrow.. anyone care to help me some.. please?

Let C = the matrix of the rotation, then
C = [ cosPI/6 sinPI/6
-sinPI/6 cosPI/6 ]
= [ sqrt(3)/4 1/2
-1/2 sqrt(3)/4 ]

Now B = A C.


I'm stuck on ideals at the moment.

Definition Let R be a commutative ring with 1. A subset I of R is an ideal if I is an additive subgroup of R and r*s is in I for all r in R and s in I.

(A ring is an abelian additive group with an associative multiplication that distributes over the addition. For an example take the integers with normal addition and multiplication. Commutative means a*b = b*a, and with 1 means there is an element e such that a*e = e*a = e, write e = 1.)

 

[Willing and Unsure]

I'm stuck on ideals at the moment.

Definition Let R be a commutative ring with 1. A subset I of R is an ideal if I is an additive subgroup of R and r*s is in I for all r in R and s in I.

(A ring is an abelian additive group with an associative multiplication that distributes over the addition. For an example take the integers with normal addition and multiplication. Commutative means a*b = b*a, and with 1 means there is an element e such that a*e = e*a = e, write e = 1.)

okay.. i get the rotation thing.. but what do ideals have to do with this problem (we havent learned anything bout them in class yet)?

 

[JilloryIsMoist]

My penis is bigger than yours. Deal with it.

 

[claude_moveml]

what do ideals have to do with this problem?

Nothing, you lucky lucky thing

 

[riff]

Re: WOW! SL good looking and brains

the total package I would say.

btw weren't riff's problems more in the realm of applied physics??
Just asking..........


SM

irational numbrs