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1. Would need help in finding x plz
2. rearrange everything and make it in terms of 2:
2^3x = (2^1/2)/(2^5)
equate the indices : 3x = -4.5
x=-1.5
3. (Original post by Bence9912)
Would need help in finding x plz
Multiply both sides by root(8)
Write everything as powers of 8
Use rules of indices to simplify the powers.

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4. (Original post by Sydian)
rearrange everything and make it in terms of 2:
2^3x = (2^1/2)/(2^5)
equate the indices : 3x = -4.5
x=-1.5
How did you rearrange?
5. (Original post by Bence9912)
How did you rearrange?
multiply both sides by root 8, rationalise the right hand side, at this point i have
8^x = root 2 / 32

ie 2^3x = 2^1/2 / 2^5
6. (Original post by Bence9912)
Would need help in finding x plz
times both sides by root 8 so 8^x = root 8 / 64. root 8/64 is the same as root 2/32 (surds and simplifying). which can be further simplified to 2^-9/2 due to the rule of indices(2^1/2 / 2^5). so 8^x = 2^-9/2. 8^x is the same as (2^x)^3 so therefore 2^x = cube root of 2^-9/2 = 2^-3/2. so 2^x = 2^-3/2. x = -3/2.
7. Get it in terms of powers of 8 is the easiest way, so you rearrange to get and then comparing both sides shows x = -1.5

You don't need to put it in powers of 2, or work with surds!

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