solving for x without a calculator

Watch
username4221054
Badges: 13
Rep:
?
#1
Report Thread starter 2 years ago
#1
4^(2x+1) = 8^(4x)

??????
i only know how to do it using log
0
reply
_gcx
Badges: 21
Rep:
?
#2
Report 2 years ago
#2
Hint: 4 = 2^2 and 8 = 2^3.

You don't need logs for this.
0
reply
username4221054
Badges: 13
Rep:
?
#3
Report Thread starter 2 years ago
#3
(Original post by _gcx)
Hint: 4 = 2^2 and 8 = 2^3.

You don't need logs for this.
oh so you make them the same base first.
thanks. i feel a bit dumb lool
0
reply
ibyghee
Badges: 19
Rep:
?
#4
Report 2 years ago
#4
(Original post by earthworm206)
oh so you make them the same base first.
thanks. i feel a bit dumb lool
dunt lul, simple mistakes to fix.
0
reply
_gcx
Badges: 21
Rep:
?
#5
Report 2 years ago
#5
(Original post by earthworm206)
oh so you make them the same base first.
thanks. i feel a bit dumb lool
Yup then you can just equate exponents.

No problem.
0
reply
RDKGames
Badges: 20
Rep:
?
#6
Report 2 years ago
#6
(Original post by earthworm206)
oh so you make them the same base first.
thanks. i feel a bit dumb lool
Well if you want to use logs nobody is stopping you, but it's clearly not the neatest.

(2x+1) \log 4 = 4x \log 8

then rearrange for x.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Current uni students - are you thinking of dropping out of university?

Yes, I'm seriously considering dropping out (88)
13.9%
I'm not sure (30)
4.74%
No, I'm going to stick it out for now (199)
31.44%
I have already dropped out (14)
2.21%
I'm not a current university student (302)
47.71%

Watched Threads

View All
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise