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Original Question
How does rationalizing the denominator use the form of 1?Asked by grace
How does rationalizing the denominator use the form of 1?
Answers
Answered by
Steve
you can always multiply by 1 without changing the value. So, you want something that makes the denominator rational.
(3+√7)/(2-√7) * (2+√7)/(2+√7)
= (3+√7)(2+√7) / (2-√7)(2+√7)
= (13+5√7)/-3
(2-3i)/(6+i) * (6-i)/(6-i)
= (2-3i)(6-i) / (6+i)(6-i)
= (15-20i)/37
(3+√7)/(2-√7) * (2+√7)/(2+√7)
= (3+√7)(2+√7) / (2-√7)(2+√7)
= (13+5√7)/-3
(2-3i)/(6+i) * (6-i)/(6-i)
= (2-3i)(6-i) / (6+i)(6-i)
= (15-20i)/37