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1. 12^x * 3^3x = 18

and

2^(xsquared-x) = 64

for that one I tried x^2 - x = 6 but I cant get the answer of 3x-2 they are looking for

thanks
2. for the first one, try expressing the LHS as (something)^x=18, then think of roots...(or you could take natural logs of both sides and simplify for x)

for the 2nd one, express 64 as powers of 2, i.e, 64 = 2^(something), and equate x^2-x to "something" - then solve the resulting quadratic.
3. (Original post by Hasufel)
for the first one, try expressing the LHS as (something)^x=18, then think of roots...(or you could take natural logs of both sides and simplify for x)

for the 2nd one, express 64 as powers of 2, i.e, 64 = 2^(something), and equate x^2-x to "something" - then solve the resulting quadratic.
thats what I did for the second one but I am not getting the answer they require and I have put the quadratic in wolframalpha and it is not giving the soloution they require either..

4. So

So or

An answer of doesn't even make sense...
5. (Original post by Noble.)

So

So or

An answer of doesn't even make sense...
It makes perfect sense its just wrong lol
6. (Original post by Noble.)

So

So or

An answer of doesn't even make sense...
I got x=3 or -2 but my book seems to think different...

So it's the former then?:P

Are you a math student at oxford?
I got x=3 or -2 but my book seems to think different...

So it's the former then?:P

Are you a math student at oxford?
Yes to both questions.
8. (Original post by Noble.)
Yes to both questions.
wow that's pretty awesome that one of the top mathematicians in the UK is helping me with my maths thanks dude
9. (Original post by Noble.)

So

So or

An answer of doesn't even make sense...
how can I simplify this? :/

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