MathB.in
New
Demo
Tutorial
About
It’s one of those “15–30–45” geometry snags where the two rays at the bottom make 30° and 45° with the horizontal but subtend a 15° gap at the top. A quick way to see why \(x\) comes out 30° is to place the apex at \((0,h)\) and let the two known rays meet the \(x\)‐axis at the points where their slopes (i.e.\ \(-\tan 30^\circ\) and \(-\tan 45^\circ\)) intersect that axis. A little slope‐difference or tangent subtraction shows the total apex angle between those two rays is actually 15°, so if the middle ray carves off 15° from one side, it leaves 30° on the other. Hence \(x=30^\circ\).
ERROR: JavaScript must be enabled to render input!
Sat, 15 Feb 2025 07:01 GMT