Question

(√3+√7) (√3-√7) pl and me
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Answer 1

- 4

Explanation:

(
`√(3)` +
`√(7)` )(
`√(3)` -
`√(7)` )

each term in the second factor is multiplied by each term in the first factor.

`√(3)` (
`√(3)` -
`√(7)` ) +
`√(7)` (
`√(3)` -
`√(7)` ) ← distribute parenthesis

= 3 -
`√(21)` +
`√(21)` - 7 ← collect like terms

= - 4

Answer 2

`\left( \sqrt 3 + \sqrt 7\right) \left( \sqrt 3 - \sqrt 7\right)\\\\=\left(\sqrt 3 \right)^2 - \left(\sqrt 7 \right)^2\\ \\=3-7\\\\=-4`