Answer:
[tex](\sqrt{6}+\sqrt{3})(\sqrt{6}-\sqrt{3})=3[/tex]
[tex](\sqrt{5}-\sqrt{2})(\sqrt{2}+\sqrt{5})=3[/tex]
Step-by-step explanation:
We want to simplify the expression:
[tex](\sqrt{6}+\sqrt{3})(\sqrt{6}-\sqrt{3})[/tex]
Notice that this is the difference of two squares pattern. Namely:
[tex]a^2-b^2=(a+b)(a-b)[/tex]
If we let a = √6 and b =√3, we acquire:
[tex](a+b)(a-b)[/tex]
Expand accordingly:
[tex]=a^2-b^2[/tex]
Back-substitute:
[tex]=(\sqrt{6})^2-(\sqrt{3})^2[/tex]
Simplify:
[tex]=6-3=3[/tex]
For the second expression, we have a similar pattern:
[tex](\sqrt{5}-\sqrt{2})(\sqrt{2}+\sqrt{5})[/tex]
We can first rewrite the expression (commutative property):
[tex]=(\sqrt{5}-\sqrt{2})(\sqrt{5}+\sqrt{2})[/tex]
And if we let a = √5 and b = √2:
[tex]=(a-b)(a+b)[/tex]
Expand accordingly:
[tex]=a^2-b^2[/tex]
Back-substitute and simplify:
[tex]=(\sqrt{5})^2-(\sqrt{2})^2=5-2=3[/tex]
