Question

solve e^2x-3e^x+2=0 for x

Answer 1

this is an equation that can be reduced to a quadratic

let \[u = e^x\] to start

then you have

\[u^2 -3u + 2 = 0\]

which can be factored

\[(u -2)(u-1) = 0\]

so u = 2, 1

then reversing the substitution

\[e^x = 2..... and..... e^x = 1\]

take the ln on both equations to find the value of x

Answer 2

@campbell_st so would it be ln2 +ln1

Answer 3

yep... but ln(1) = 0

so x = 0 or ln(2)

Answer 4

and no plus sign between them.

Answer 5

oh okay :] @campbell_st can you help me with another one? it says solve logx +log (x-1)=log 4x for x.

Answer 6

sorry i have to go to school..

post it and there are lots of people here who can help.

Answer 7

okay well thanks for your help @campbell_st