Question

Simplify (root 11 + root 5 ) (root 11 - root 5)

Answer 1

Dear Student,


$$\begin{gathered} \mathrm{Using}\mathrm{identity}\left(\mathrm{a}+\mathrm{b}\right)\left(\mathrm{a}-\mathrm{b}\right)={\mathrm{a}}^2-{\mathrm{b}}^2 \\ \left(\sqrt{11}+\sqrt{5}\right)\left(\sqrt{11}-\sqrt{5}\right) \\ ={\left(\sqrt{11}\right)}^2-{\left(\sqrt{5}\right)}^2 \\ =11-5 \\ =6\mathrm{ANS}... \end{gathered}$$

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