Powers and roots
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Guesswork
Ask a friend to choose a number between 1 and 63. By identifying which of the six cards contains the number they are thinking of it is easy to tell them what the number is.
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Ab surd ity
Find the value of sqrt(2+sqrt3)-sqrt(2-sqrt3)and then of
cuberoot(2+sqrt5)+cuberoot(2-sqrt5).
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Perfectly square
The sums of the squares of three related numbers is also a perfect square - can you explain why?
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Power mad!
Powers of numbers behave in surprising ways. Take a look at some of these and try to explain why they are true.
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Power countdown
In this twist on the well-known Countdown numbers game, use your knowledge of Powers and Roots to make a target.
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Em'power'ed
Find the smallest numbers a, b, and c such that: a^2 = 2b^3 = 3c^5
What can you say about other solutions to this problem?
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Number rules - ok
Can you produce convincing arguments that a selection of statements about numbers are true?