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# C3 how do i solve these equations watch

1. ln(x+4) = ln(2x-3)

and

e^(4x+1) = e^(1-x)

2. First one drop the ln's, my dog can solve x + 4 = 2x - 3

Second one take natural logs of both sides to get 4x + 1 = 1 - x

Again, my dog can solve that so i'm sure you can too.

3. (Original post by *MJ*)
First one drop the ln's, my dog can solve x + 4 = 2x - 3

Second one take natural logs of both sides to get 4x + 1 = 1 - x

Again, my dog can solve that so i'm sure you can too.

Seriously? My dogs can't even sit.
4. (Original post by Tallon)
Seriously? My dogs can't even sit.
Yeah but that's because you didn't bring him over from Bangladesh on a banana boat, did you?
5. (Original post by *MJ*)
Yeah but that's because you didn't bring him over from Bangladesh on a banana boat, did you?
Apparently the dogs in Bangladesh have gills. Differential reproductive success or something.
6. (Original post by SeekerOfKnowledge)
ln(x+4) = ln(2x-3)

and

e^(4x+1) = e^(1-x)

or if it wants u to simplify them, you can take the one on the right and bring it over....to get ln(x+4) - ln(2x-3) and then have ln(x+4/2x-3)=0
7. (Original post by Tallon)
Seriously? My dogs can't even sit.

8. (Original post by SK-mar)
or if it wants u to simplify them, you can take the one on the right and bring it over....to get ln(x+4) - ln(2x-3) and then have ln(x+4/2x-3)=0
What's the point?

You're going to end up with what I posted above.

ln(x+4/2x-3) = 0

(x+4/2x-3) = e^0

(x+4/2x-3) = 1

x+4 = 2x-3

^^^ Why not just drop the ln's and get that straight away?

9. (Original post by *MJ*)
What's the point?

You're going to end up with what I posted above.

ln(x+4/2x-3) = 0

(x+4/2x-3) = e^0

(x+4/2x-3) = 1

x+4 = 2x-3

^^^ Why not just drop the ln's and get that straight away?

ha just making sure he gets where your coming from with dropping the natural logs.....btw ive just posted a thread about a trig problem im facing, you seem like a clever lad, would you give it a look please...I will rep if the answer is clear and makes sense to moi....cheers
10. (Original post by *MJ*)
First one drop the ln's, my dog can solve x + 4 = 2x - 3

Second one take natural logs of both sides to get 4x + 1 = 1 - x

Again, my dog can solve that so i'm sure you can too.

oh i didnt know you drop the ln and the e^
thanks
11. (Original post by SK-mar)
ha just making sure he gets where your coming from with dropping the natural logs.....btw ive just posted a thread about a trig problem im facing, you seem like a clever lad, would you give it a look please...I will rep if the answer is clear and makes sense to moi....cheers

12. (Original post by SeekerOfKnowledge)
oh i didnt know you drop the ln and the e^
thanks
No problem.

As long as you remember it in future, all is well.
13. ln(x+4)-ln(2x-3)=0
ln(x+4/2x-3)=0
multiply by (e)
x+4/2x-3=1
x=7

e^(4x+1)=e^(1-x)
multiply by ln both sides
4x+1=1-x
x=0
14. (Original post by Hippysnake)
Apparently the dogs in Bangladesh have gills. Differential reproductive success or something.
Survival of the fittest resulted in the dogs mating with fish so their offspring could breathe on land *and* underwater.
15. (Original post by *MJ*)
Yeah but that's because you didn't bring him over from Bangladesh on a banana boat, did you?

No. No, I did not. Thats why I can't teach my dog maths.
16. (Original post by Ignoramus)
Survival of the fittest resulted in the dogs mating with fish so their offspring could breathe on land *and* underwater.
But as the water rises, those with gills have greater reproductive success, increasing the allele frequency for gills.
17. I'm scared of C3 tbh

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