Rationalize the denominator.
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Answer:
7sqrt(15) - 5sqrt(6)
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45
Step-by-step explanation:
7 -sqrt(10)
-----------------------
3 sqrt(5) *sqrt(3)
7 -sqrt(10)
-----------------------
3 sqrt(15)
Multiply the top and bottom by sqrt(15)/ sqrt(15)
7 -sqrt(10) sqrt(15)
----------------------- * ------------
3 sqrt(15) sqrt(15)
(7 -sqrt(10))* sqrt(15)
-----------------------------------
3 *15
Distribute
7sqrt(15) - sqrt(150)
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45
sqrt(ab) =sqrt(a) sqrt(b)
150 = 25*6
7sqrt(15) - sqrt(25)sqrt(6)
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45
7sqrt(15) - 5sqrt(6)
------------------------------
45
Answer:
21√15 - 15√6 / 135
Step-by-step explanation: First multiply 3√5 with √3 to get 3√15. Then rationalize to get to 21√15 - 3√150 as the numerator. Simplify 3√150 to 15√6, and then you get an answer of 21√15 - 15√6 / 135.