simplify sqrt(4-sqrt(7))+sqrt(8+3sqrt(7))
\[\sqrt{4-\sqrt{7}}+\sqrt{8+3\sqrt{7}}\]
Is that the problem?
ya
its answer is given as sqrt(2)(sqrt(7)+1) bt how its so???
I'm going to have to work on it a little bit.
k,thnks in advance
From Wolf: \[\sqrt{4-\sqrt{7}}=\frac{\sqrt{7}-1}{\sqrt{2}}\]
And \[\sqrt{8+3\sqrt{7}}=\frac{3+\sqrt{7}}{\sqrt{2}}\]
But I haven't been able to figure out how they get that. Sorry.
I hope you come back and check for a solution: \[\sqrt{4-\sqrt{7}}=\sqrt{\frac{8-2\sqrt{7}}{2}}=\sqrt{\frac{7-2\sqrt{7}+1}{2}}=\]
\[\sqrt{\frac{(\sqrt{7}-1)^2}{2}}=\frac{\sqrt{7}-1}{\sqrt{2}}\]
Similarly\[\sqrt{8+3\sqrt{7}}=\sqrt{\frac{16+6\sqrt{7}}{2}}=\sqrt{\frac{9+6\sqrt{7}+7}{2}}=\]
\[\sqrt{\frac{(3+\sqrt{7})^2}{2}}=\frac{3+\sqrt{7}}{\sqrt{2}}\]
And so adding the two: \[\frac{\sqrt{7}-1}{\sqrt{2}}+\frac{3+\sqrt{7}}{\sqrt{2}}=\frac{2\sqrt{7}+2}{\sqrt{2}}=\]
\[\frac{2^1(\sqrt{7}+1)}{2^{\frac{1}{2}}}=2^{\frac{1}{2}}(\sqrt{7}+1)=\sqrt{2}(\sqrt{7}+1)\]
Hope this helps @Arunp
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