This means we multiply the first terms in each binomial, then the outer terms, then the inner terms, and finally the last terms in each binomial.
So, we have:
\[ (2 \sqrt{7}+3 \sqrt{5})(\sqrt{7}-2 \sqrt{5}) = 2\sqrt{7} \cdot \sqrt{7} - 2\sqrt{7} \cdot 2\sqrt{5}
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