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Teachers & SchoolsMathematical Reasoning: Drill Set 2, Problem 2. A positive integer, n, when squared, is always greater than or equal to the doubling of n, except when n equals...what?

CAHSEE Math | Mathematical Reasoning |

Exponents and Radicals | Integer Exponents |

Language | English Language |

Mathematical Reasoning | Generalizing results |

see whether we can conceive the theory of n in our brain.

When we get these kinds of problems, always

try 0 first because it's usually really easy to manipulate.

Then 1. Then negative 1. Then a fraction. Annnnnd we're done. Usually.

In this case, note the word ALWAYS and greater than or equal to...

It's giving us the equation n squared is greater than or equal to 2n.

True for 0. True for 2. True for 4. True for one half? No.

Try 1. Well, 2n is 2 and 1 squared is...1. So it's the only one that's NOT true --

And the answer is A.