171k views
2 votes
Expand and simplify

(√15-√3)²
Give your answer in the form b-c√5
where b and c are integers.

User Shelper
by
4.4k points

1 Answer

6 votes


= ( √(15) - √(3) )( √(15) - √(3) ) \\ = √(15) ( √(15) - √(3) ) - √(3) ( √(15) - √(3) ) \\ = 15 - √(45) - √(45) + 3 \\ = 15 + 3 - 2 √(45) \\ = 18 - 2( √(9 * 5) ) \\ = 1 - 2(3 √(5) ) \\ = 1 - 6 √(5)

ATTACHED IS THE SOLUTION

User David SK
by
4.4k points