# Indices problem

1. Dec 16, 2009

### 1/2"

1. The problem statement, all variables and given/known data
The problem is 4 x+ 3*2 x+2 + 32 = 0

2. Relevant equations
None

3. The attempt at a solution
I can’t get to any solution in this problem but I have come to a point (if it is nearing any solution though) but I am not sure whether it is correct or not.
Well what I have done is
2 2x + (2+1)2 x+2 + 2 5=0
==> 2 2x + 2*2 x+2 + 2 x+2 +2 5=0
==>2 2x + 2 x+3 + 2 x+2 +2 5=0
( That’s all I have done)
I would be very thankful to receive any help!!
Thank you!!

Last edited: Dec 16, 2009
2. Dec 16, 2009

### Staff: Mentor

4x = (22)x = 22x and 2x + 2 = 22* 2x

Your equation can be rewritten so that it is quadratic in form.

3. Dec 16, 2009

### 1/2"

Ok so I write it like this
2 2x + 2 x*2 3 + 2 x *2 2 +2 5=0
But where does it go after this??

4. Dec 16, 2009

### annoymage

you see, that 2^x is the common variable,
so you can solve it like solving quadratic equation..

or if you wan to see it more clearly, try let u = 2^x

5. Dec 16, 2009

### Staff: Mentor

your coefficient of 2x is wrong. There should be only a single 2x term, not two of them as you show. 3*2x+2 does NOT expand to a sum of two terms.

Also, rewriting 32 as 25 does you no good.