MathDB
Telescoping product

Source: 1959 AHSME Problem 37

August 14, 2013
AMCtelescopeProductalgebraAMC 12

Problem Statement

When simplified the product (113)(114)(115)(11n)\left(1-\frac13\right)\left(1-\frac14\right)\left(1-\frac15\right)\cdots\left(1-\frac1n\right) becomes: <spanclass=latexbold>(A)</span> 1n<spanclass=latexbold>(B)</span> 2n<spanclass=latexbold>(C)</span> 2(n1)n<spanclass=latexbold>(D)</span> 2n(n+1)<spanclass=latexbold>(E)</span> 3n(n+1) <span class='latex-bold'>(A)</span>\ \frac1n \qquad<span class='latex-bold'>(B)</span>\ \frac2n\qquad<span class='latex-bold'>(C)</span>\ \frac{2(n-1)}{n}\qquad<span class='latex-bold'>(D)</span>\ \frac{2}{n(n+1)}\qquad<span class='latex-bold'>(E)</span>\ \frac{3}{n(n+1)}