If (a=\sqrt{3}+2) and (b=\sqrt{3}-2), what is the value of (ab)?
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Answer and explanation
Correct answer: (-1)
Step 1: (ab=(\sqrt{3}+2)(\sqrt{3}-2)). Step 2: Using difference of squares, ((\sqrt{3})^2-2^2=3-4=-1). Step 3: Recognising conjugate form makes the calculation shorter.
Frequently asked questions
What is the correct answer to this question?
(-1)
Why is this the correct answer?
Step 1: (ab=(\sqrt{3}+2)(\sqrt{3}-2)). Step 2: Using difference of squares, ((\sqrt{3})^2-2^2=3-4=-1). Step 3: Recognising conjugate form makes the calculation shorter.
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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