squaring the circle
... that although the problem of squaring the circle with compass and straightedge goes back to Greek mathematics, it was not proven impossible until 1882?
... that although the problem of <b id="mwBdA"><a href="./Squaring_the_circle" id="mwBdE" rel="mw:WikiLink" title="Squaring the circle">squaring the circle</a></b> with <a href="./Straightedge_and_compass_construction" id="mwBdI" rel="mw:WikiLink" title="Straightedge and compass construction">compass and straightedge</a> goes back to <a href="./Greek_mathematics" id="mwBdM" rel="mw:WikiLink" title="Greek mathematics">Greek mathematics</a>, it was not proven impossible until 1882?