If (a=\sqrt{2}+1) and (b=\sqrt{2}-1), what is the value of (ab)?
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Answer and explanation
Correct answer: (1)
Step 1: (ab=(\sqrt{2}+1)(\sqrt{2}-1)). Step 2: Using difference of squares, ((\sqrt{2})^2-1^2=2-1=1). Step 3: Learn to recognise conjugate forms like (a+b) and (a-b).
Frequently asked questions
What is the correct answer to this question?
(1)
Why is this the correct answer?
Step 1: (ab=(\sqrt{2}+1)(\sqrt{2}-1)). Step 2: Using difference of squares, ((\sqrt{2})^2-1^2=2-1=1). Step 3: Learn to recognise conjugate forms like (a+b) and (a-b).
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Real Numbers. Topic: Irrational numbers.
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