Question

Упростите выражение (4+√a)(4-√a)

Answer 1

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$\displaystyle \bf Formula: \left(a+b\right)\left(a-b\right)=a^2-b^2\\ \\\\\Big(4+\sqrt{a}\Big)\Big(4-\sqrt{a}\Big)=\Big(4\Big)^2-\Big(\sqrt a\Big)^2=\Big(4\cdot 4\Big)-\Big(\sqrt a \cdot \sqrt a\Big)=16-a$