Write
\( \sqrt{75} - \sqrt{27} \)
in the form \( k \sqrt{x} \), where \( k \) and \( x \) are integers. - Edexcel - A-Level Maths Pure - Question 3 - 2010 - Paper 1
Question 3
Write
\( \sqrt{75} - \sqrt{27} \)
in the form \( k \sqrt{x} \), where \( k \) and \( x \) are integers.
Worked Solution & Example Answer:Write
\( \sqrt{75} - \sqrt{27} \)
in the form \( k \sqrt{x} \), where \( k \) and \( x \) are integers. - Edexcel - A-Level Maths Pure - Question 3 - 2010 - Paper 1
Step 1
Step 1: Simplifying \( \sqrt{75} \)
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Answer
To simplify ( \sqrt{75} ), we can factor it as:
75=25⋅3=25⋅3=53
Step 2
Step 2: Simplifying \( \sqrt{27} \)
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Answer
Similarly, we simplify ( \sqrt{27} ):
27=9⋅3=9⋅3=33
Step 3
Step 3: Combining the terms
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Answer
Now we can substitute these results into our original expression:
75−27=53−33=(5−3)3=23
This gives us the final result in the required form ( k\sqrt{x} ) where ( k = 2 ) and ( x = 3 ).