Differential equation

[edwerg]

Help, I need to know how to solve the differential equation dy/dx = (secx tanx) /(secx +5) I know the solution is y=ln|secx + 5| + C but I do not get the procedure. thank you for your help.

 

[tridelta246]

Help, I need to know how to solve the differential equation dy/dx = (secx tanx) /(secx +5) I know the solution is y=ln|secx + 5| + C but I do not get the procedure.

Rewrite the equation:
dy = (secx tanx) /(secx +5) dx
Now integrate both sides.

.

 

[edwerg]

Thank you, I know the first part, my problem (I guess I should have been more specific ) is i am having problems taking the integral

 

[Gene]

Remember d(ln(u)) = d(u)/u and look up
d(sec(u))

BTW it would be nice to buy a lot of ()s. K-mart is having a sale. Then you can say
dy/dx = (sec(x) tan(x)) /sec(x +5) or
dy/dx = (sec(x) tan(x)) /(sec(x) +5)
It isn't necessary in this one but you should always use tnem to indicate where functions end.
(secx +5) means add 5 to sec(x) which is different than add 5 to x then take the secant of that. We have to be sure which you mean.

 

[edwerg]

Sorry about the missing ()'s, thank you for your help. Got it now.

 

[Makayla52]

Awareness

Be sure to check it yourself, trusting others might not always be the smartest thing to do.

 

[stapel]

Re: Awareness

...trusting others might not always be the smartest thing to do.

Like trusting losers who sign up to forums just to post ads for their casino sites...? Yeah, that probably wouldn't be a good idea.... :roll:

Eliz.