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Simplify 3/√7 - √2.

A) √7 - 2√2
B) √7 - √2
C) √7 + √2
D) √7 - √14

User Burrell
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1 Answer

5 votes

Final answer:

The simplified form of 3/√7 - √2 is √7 - √14. So, option D is correct.

Step-by-step explanation:

To simplify the expression 3/√7 - √2, let's rationalize the denominator of the first term. Multiply both the numerator and denominator of the fraction by the conjugate of the denominator:


\[ (3)/(√(7)) \cdot (√(7))/(√(7)) = (3√(7))/(7) \]

Now, the expression becomes
\( (3√(7))/(7) - √(2) \). To combine the terms, find a common denominator, which is 7:


\[ (3√(7))/(7) - (7√(2))/(7) = (3√(7) - 7√(2))/(7) \]

Now, you can factor out the common factor of √7 from the numerator:


\[ (√(7)(3 - 7√(2)/√(7)))/(7) \]

Simplify further:


\[ (√(7)(3√(7) - 7√(2)))/(7) \]

Finally, cancel out the common factor of √7:


\[ 3 - 7√(2) \]

So, the simplified expression is
\( √(7) - √(14) \), which corresponds to option D.

User Kelle
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8.5k points