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How do you solve this? 

 

ex - 6e-x = 1

 Oct 6, 2015

Best Answer 

 #2
avatar+118702 
+15

ex - 6e-x = 1

 

ex6ex=1ex6ex=1ex(ex6ex)=1ex(ex)26=ex(ex)2ex6=0suby=exy2y6=0(y3)(y+2)=0y=3ory=2ex=3orex=2lnex=ln3ornosolutionx=ln3

 Oct 6, 2015
 #1
avatar+130477 
+15

ex - 6e-x = 1      multiply through by ex

 

e2x - 6 = ex      subtract  ex  from both sides and rearrange the left side

 

e2x - ex - 6 =  0     factor this

 

(ex - 3) (ex + 2) =     setting each factor to 0, we have

 

ex - 3 = 0                                   and                             ex + 2 = 0

 

The second equation has no solution.....for the first, we have

 

ex - 3 = 0

 

Add 3 to both sides

 

ex  = 3       take the ln of both sides

 

ln e= ln 3      and we can write

 

x ln e =   ln 3     and ln e = 1, so we can ignore this.......and we have

 

x = ln 3 = about 1.0986

 

 

cool cool cool

 Oct 6, 2015
 #2
avatar+118702 
+15
Best Answer

ex - 6e-x = 1

 

ex6ex=1ex6ex=1ex(ex6ex)=1ex(ex)26=ex(ex)2ex6=0suby=exy2y6=0(y3)(y+2)=0y=3ory=2ex=3orex=2lnex=ln3ornosolutionx=ln3

Melody Oct 6, 2015
 #3
avatar+130477 
+5

HAHAHAHAHA!!!!!!!!.......beat you, Melody   !!!!!!    LOL!!!!!!!

 

 

 

 

cool cool cool

 Oct 6, 2015

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