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# Differential equations

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1. For (1-cost)(dx/dt) = sintcotx
I got the answer to be secx=A/(1-cost), whereas the book says secx=A(1-cost)?
2. (Original post by pippabethan)
For (1-cost)(dx/dt) = sintcotx
I got the answer to be secx=A/(1-cost), whereas the book says secx=A(1-cost)?
I think the book is right, mind posting your working?
3. (Original post by pippabethan)
For (1-cost)(dx/dt) = sintcotx
I got the answer to be secx=A/(1-cost), whereas the book says secx=A(1-cost)?
Got any workings?
4. (ignore the tick, I did that before I realised it was different)
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5. (Original post by pippabethan)
(ignore the tick, I did that before I realised it was different)
integrated the RHS wrong, no minus sign needed
6. (Original post by pippabethan)
(ignore the tick, I did that before I realised it was different)
As above, remember that . So no need for the minus.
7. (Original post by Zacken)
As above, remember that . So no need for the minus.
Ooops, I completely missed that thank you!

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