Answer:
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Given expression:
[tex]\dfrac{\sqrt{14} }{\sqrt{7}-2} -\dfrac{\sqrt{14} }{\sqrt{7}+2}[/tex]
Simplify it in steps:
Step 1
Bring both fractions into common denominator:
[tex]\dfrac{\sqrt{14} (\sqrt{7}+2)}{(\sqrt{7}-2)(\sqrt{7}+2)} - \dfrac{\sqrt{14} (\sqrt{7}-2)}{(\sqrt{7}-2)(\sqrt{7}+2)}[/tex]
Step 2
Simplify:
[tex]\dfrac{\sqrt{14} ((\sqrt{7}+2) - (\sqrt{7}-2))}{(\sqrt{7}-2)(\sqrt{7}+2)} =[/tex]
[tex]\dfrac{\sqrt{14} (\sqrt{7}+2 - \sqrt{7}+2)}{(\sqrt{7}-2)(\sqrt{7}+2)} =[/tex]
[tex]\dfrac{4\sqrt{14} }{(\sqrt{7}-2)(\sqrt{7}+2)} =[/tex]
[tex]\dfrac{4\sqrt{14} }{(\sqrt{7})^2-2^2} =[/tex]
[tex]\dfrac{4\sqrt{14} }{7-4} =[/tex]
[tex]\dfrac{4}{3} \sqrt{14} }[/tex]
Step 3
Compare the result with given expression to get:
