By using y=2^x or otherwise, solve

4^x - 3 (2^(x+1)) + 8= o

so i understand to convert the 4^x to 2^x(2) but how to proceed ??

sorry cant type equations properly dont know what language this forums use and again sorry.

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- May 5th 2012, 07:42 PMmathkid12Indices past paper question help
By using y=2^x or otherwise, solve

4^x - 3 (2^(x+1)) + 8= o

so i understand to convert the 4^x to 2^x(2) but how to proceed ??

sorry cant type equations properly dont know what language this forums use and again sorry. - May 5th 2012, 07:51 PMProve ItRe: Indices past paper question help
$\displaystyle \displaystyle \begin{align*} 4^x - 3 \cdot 2^{x + 1} + 8 &= 0 \\ \left( 2^2 \right) ^x - 3 \cdot 2 \cdot 2^x + 8 &= 0 \\ 2^{2x} - 6 \cdot 2^x + 8 &= 0 \\ \left( 2^x \right) ^2 - 6 \cdot 2^x + 8 &= 0 \\ X^2 - 6X + 8 &= 0 \textrm{ after making the substitution } X = 2^x \end{align*}$

You should now be able to solve. - May 5th 2012, 08:05 PMmathkid12Re: Indices past paper question help
thanks, thank you very very much!!!!!!!!1