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Core 1 - Indices question help

Hi there,

I have a question:

2^(x) * 4^(x+1) = 8


According to a mark scheme, the answer is x = 1/3 but I don't understand how. Any help would be vastly appreciated.
Original post by CantonHero
...


4=22 4=2^2 and 8=23 8=2^3

Good luck. :smile:
Reply 2
Avatar for CantonHero
CantonHero
OP
3
Even with that, I get x to equal 0
Original post by CantonHero
...


Show working? :smile:
Can you show that: 2x4x+1=22+3x 2^x 4^{x+1} = 2^{2+3x} ?
Reply 5
Avatar for LypeX
LypeX
Original post by lazy_fish
Show working? :smile:


2^x * 4^(x+1) = 8 Original
2^x * (2^2)^(x+1) = 2^3 Simplify to get all 2^y
2^x * 2^(2x+2) = 2^3 Expand
2^(3x+2) = 2^3 Rule of indices

This means that 3x+2 = 3

3x = 1

x=1/3


Might be too late but eh, we're all in this together.

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