Formulate a conjecture (with an appropriate quantifier) that can be used as an answer to each of the following questions.
For which natural numbers is greater than ?
정답·풀이 보기 (영어 원문)
For each natural number , if , then .
한 번 더 — 비슷한 문제Sundstrom, Mathematical Reasoning · 4.1절 · 14번영어 원문
Use mathematical induction to prove that the sum of the cubes of any three consecutive natural numbers is a multiple of 9.
다 풀었으면 정답 확인
Three consecutive natural numbers may be represent by , , and , where is a natural number. For the inductive step, think before you try to do a lot of algebra. You should be able to complete a proof of the inductive step by expanding the cube of only one expression.