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Rationalising The Denominator (1 Viewer)

Dan895

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3sqrt2-4/3sqrt2+4

I can't manage to work out how to rationalise this, some help would be super. Thanks
 

deswa1

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<a href="http://www.codecogs.com/eqnedit.php?latex=\frac{3\sqrt{2}-4}{3\sqrt{2}@plus;4}=\frac{(3\sqrt{2}-4)(3\sqrt{2}-4)}{(3\sqrt{2}@plus;4)(3\sqrt{2}-4)} \\=\frac{18-24\sqrt{2}@plus;16}{18-16}\\ =\frac{34-24\sqrt{2}}{2}\\ =17-12\sqrt{2}" target="_blank"><img src="http://latex.codecogs.com/gif.latex?\frac{3\sqrt{2}-4}{3\sqrt{2}+4}=\frac{(3\sqrt{2}-4)(3\sqrt{2}-4)}{(3\sqrt{2}+4)(3\sqrt{2}-4)} \\=\frac{18-24\sqrt{2}+16}{18-16}\\ =\frac{34-24\sqrt{2}}{2}\\ =17-12\sqrt{2}" title="\frac{3\sqrt{2}-4}{3\sqrt{2}+4}=\frac{(3\sqrt{2}-4)(3\sqrt{2}-4)}{(3\sqrt{2}+4)(3\sqrt{2}-4)} \\=\frac{18-24\sqrt{2}+16}{18-16}\\ =\frac{34-24\sqrt{2}}{2}\\ =17-12\sqrt{2}" /></a>
 

Timske

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<a href="http://www.codecogs.com/eqnedit.php?latex=\frac{3\sqrt{2} - 4}{3\sqrt{2} @plus; 4} , \mathrm{\mathbf{\mathbf{\mathrm{}~multiply ~by ~it's ~conjugate}}}\\\\ \therefore ~~\frac{3\sqrt{2} - 4}{3\sqrt{2} @plus; 4} *\frac{3\sqrt{2} -4}{3\sqrt{2} - 4}" target="_blank"><img src="http://latex.codecogs.com/gif.latex?\frac{3\sqrt{2} - 4}{3\sqrt{2} + 4} , \mathrm{\mathbf{\mathbf{\mathrm{}~multiply ~by ~it's ~conjugate}}}\\\\ \therefore ~~\frac{3\sqrt{2} - 4}{3\sqrt{2} + 4} *\frac{3\sqrt{2} -4}{3\sqrt{2} - 4}" title="\frac{3\sqrt{2} - 4}{3\sqrt{2} + 4} , \mathrm{\mathbf{\mathbf{\mathrm{}~multiply ~by ~it's ~conjugate}}}\\\\ \therefore ~~\frac{3\sqrt{2} - 4}{3\sqrt{2} + 4} *\frac{3\sqrt{2} -4}{3\sqrt{2} - 4}" /></a>
 

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