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Pls help rationalize

Pls help rationalize-example-1

2 Answers

2 votes

Answer:

See answers below.

Explanation:

All of these use the same idea: multiply numerator and denominator by the conjugate radical (an identical expression but with the sign between terms changed).


(1)/(13-√(15))\cdot(13+√(15))/(13+√(15))=(13+√(15))/(169-15)}\\\\=(13+√(15))/(154)


(1)/(√(13)-√(11)) \cdot (√(13)+√(11))/(√(13)+√(11))=(√(13)+√(11))/(13-11)\\\\=(√(13)+√(11))/(2)


(1)/(√(21)+√(29))\cdot(√(21)+√(29))/(√(21)+√(29))=(√(21)+√(29))/(21-29)\\\\=(√(21)+√(29))/(-8)

Note: Here's an example of what happens when you multiply conjugate radicals.


(√(13)-√(11)})(√(13)+√(11))=13-√(11)√(13)+√(13)√(11)-11=13-11

When you FOIL those binomials, the square roots go away!

User Peter Mols
by
2.9k points
5 votes

Answer:

1= 0.109

2= 3.46

3 = -(minus)1.24

Step-by-step explanation:

User Ruwan
by
3.8k points