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Qualification => University => Topic started by: SGVaibhav on April 19, 2010, 12:34:00 pm

Title: Urgent! How to solve 2 simultaneous equations..
Post by: SGVaibhav on April 19, 2010, 12:34:00 pm
This came in applied mechanics - equilibirum of a particle...


I got  equations, and i dont know how to solve them ??

1-       2500 = TAC cos (T)
2-       500 = TAC sin (T)

for those who are confused with TAC, take it as a single variable x......
i dont know how to solve such equations...
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: Amr Fouad on April 19, 2010, 12:40:25 pm
This came in applied mechanics - equilibirum of a particle...


I got  equations, and i dont know how to solve them ??

1-       2500 = TAC cos (T)
2-       500 = TAC sin (T)

for those who are confused with TAC, take it as a single variable x......
i dont know how to solve such equations...

No worries..You cannt solve with simultaneous..it will take a long time..Divide both equations by each other...sin/cos=tan

Therefore:

tan (T)=0.2...Then use the triangle method to find the values of sin and cos..

got that?
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: T.Q on April 19, 2010, 12:44:27 pm
This came in applied mechanics - equilibirum of a particle...


I got  equations, and i dont know how to solve them ??

1-       2500 = TAC cos (T)
2-       500 = TAC sin (T)

for those who are confused with TAC, take it as a single variable x......
i dont know how to solve such equations...

Tac =500/sinT

Substitute

u will get 5sint=cost

squre all the equ. ( 5sint=cost )^2

25sin^2t=cos^2t

25sin^2t= 1-sin^2t

26sin^2t=1

sin^2t=1/26

take the squre root

sint= (1/26)^0.5
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: Amr Fouad on April 19, 2010, 12:46:31 pm
Tac =500/sinT

Substitute

u will get 5sint=cost

squre all the equ. ( 5sint=cost )^2

25sin^2t=cos^2t

25sin^2t= 1-sin^2t

26sin^2t=1

sin^2t=1/26

take the squre root

sint= (1/26)^0.5


As i said..it will take such a long time..:P mine is easier ;D
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: nid404 on April 19, 2010, 12:49:44 pm
Yes A.F's is way easier.....saves time...it's P1 stuff
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: T.Q on April 19, 2010, 12:50:18 pm
As i said..it will take such a long time..:P mine is easier ;D

ya i know  ;)


 
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: SGVaibhav on April 19, 2010, 12:56:21 pm
@T.Q... thanks i understood :D
but at times, it can get more complex...
so
@A.F ..  how did u do it?
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: nid404 on April 19, 2010, 12:59:51 pm
@T.Q... thanks i understood :D
but at times, it can get more complex...
so
@A.F ..  how did u do it?

It's P1 stuff...we do it in A level

divide the equations...so u get

500/2500 = TAC sin (T)/  TAC cos (T)

sin(T)/cos(T)=Tan (T)
Tan(T)=0.2
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: Amr Fouad on April 19, 2010, 01:00:29 pm
This came in applied mechanics - equilibirum of a particle...


I got  equations, and i dont know how to solve them ??

1-       2500 = TAC cos (T)
2-       500 = TAC sin (T)

for those who are confused with TAC, take it as a single variable x......
i dont know how to solve such equations...

Divide both equations by each other:

Tsin(T)/Tcos(T)=500/2500...The tension cancels out..

sin/cos=tan (T)
500/2500=0.2

how about now?
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: Amr Fouad on April 19, 2010, 01:01:09 pm
oooooppsss..sory nid..posted in the same time ;D ;D
Title: Re: Urgent! How to solve 2 simultaneous equations..
Post by: SGVaibhav on April 19, 2010, 01:01:47 pm
oh..
we divide :P equations..
now i understood :D :D :D
thanks everyone =)

lol
i got new reply posted twice :P