How Do I Correctly Solve This Algebraic Equation Involving e and K?

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ive got (y-1/y+2)=Ke3/4x4where K=+ or- e3c

and I am trying to get to y=(2Ke3/4x4)/(1-Ke3/4x4)

but i keep getting y= (-3+Ke3/4x4)/(Ke3/4x4) can someone please have a go at this to see if its me that's wrong or the answer sheet and if its me which it usualy is can you please write your working step by step? thanks
 
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We have:

<br /> \frac{y-1}{y+2}=KL<br />

In which K=\pm e^{3c} and L=e^{\frac{3}{4}x^4}

We now work this out:

<br /> y-1=yKL+2KL<br />

<br /> y=yKL+2KL+1<br />

<br /> y-yKL=2KL+1<br />

<br /> y(1-KL)=2KL+1<br />

<br /> y=\frac{2KL+1}{1-KL}<br />

This does not correspond to the solution you want to get, but in my opinion this is the correct one, maybe you have not given the correct question?
 
ye that's right sorry i forgot to put the +1 on the end and that way is about 50^2 times simpler than the way i was trying to do it thanks!
 
no problem :smile: sometimes the math becomes easier if you just replace some nasty crap by a single parameter :smile:
 
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