ln(3x+7)=1.31
(ln as in log natural)

Question

ln(3x+7)=1.31
(ln as in log natural)

retireed · Answer

First raise both sides by e and solve for x... 

   e^[ln(3x+7)] = e^1.31

   3x + 7 = e^1.31

chaotic_butterflies · Answer

I was afraid that might happen.. alright let me try to write it out

chaotic_butterflies · Answer

(and thank you for helping)

chaotic_butterflies · Answer

I got $$x\approx  -1.6389$$

zepdrix · Answer

Ya? Hmm my value is coming out slightly different..

zepdrix · Answer

Subtract 7,
divide 3,$$\large\rm x=\frac{e^{1.31}-7}{3}$$This is what you input?
Something similar?

retireed · Answer

i got closer to-1.097

chaotic_butterflies · Answer

I simplified e^1.31 to 2.0834 and solved algebraically from there

chaotic_butterflies · Answer

Honestly my teacher isn't a stickler, I don't think I'm too far off from your answer @retirEEd

chaotic_butterflies · Answer

Oh wait a sec, I calculated e^1.13

chaotic_butterflies · Answer

Whoops

zepdrix · Answer

Ah :D

chaotic_butterflies · Answer

I got -1.0979

chaotic_butterflies · Answer

So I got what you did @retirEEd

retireed · Answer

Try to plug in and solve for @zebdrix equation.  

Personally, I think your answer is significantly different.  I solved mine by graphing the original equation and seeing where it equalled 1.31.

retireed · Answer

Sorry I'm watching TV so my responses are running behind your answers.

chaotic_butterflies · Answer

That's fine, I'm a bit scatterbrained myself. Thanks for the help @retirEEd  @zepdrix

retireed · Answer

np