r Zuzen bat eta [math]\pi[/math]plano baten arteko angelua kalkulatzeko:[br]1. r zuzenaren norabide bektorearen eta [img]data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAALCAYAAABLcGxfAAAAk0lEQVQoU5XRMQ4BURDG8d/qFBIqOq1Kp9E6gUThCirEERyAjns4gGvoRE8UGlGIbPI2eTax8iaZZjL/mW/myyRGltivDLxwRR1NPEOeMcYlBobYo487WnijFquIgR1mGGGNOQ7o/AKK+gMrNDDFoApo4xTkLLBEtwo44oYJcmDD92PKX+qFDcXQHNr+u6HSmmTjPn4BFQyKZXxQAAAAAElFTkSuQmCC[/img] planoaren bektore normalaren arteko [math]\beta[/math]angelua kalkulatuko dugu.[br]2. ang(r,[img]data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAALCAYAAABLcGxfAAAAlUlEQVQoU5XRLQpCURCG4edGQTCI2eJCtBrsgslisQiaxTUIrsAduACNRkGrK/AHlyAHrnC84JEzMGWYd+b7ZgqZUWT2qwJXnNFAFxfcccIKrxhoY4Ep9ujhgWasIgZG2KKDMTZlDn4Bn/oRM9TQxzwF1LEr5QQPEwxTwBJPrEvTwcvXYapXauEWTQxbDv88JF+T/bg3aeUVDK46OMIAAAAASUVORK5CYII=[/img]) = [math]\alpha[/math]= 90º-[img]data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAARCAYAAADpPU2iAAAA2klEQVQ4T5XSIU+CURTG8R/VwEZkBqzwKUwUu4Jz4Nz0CxANatIghcYMFpKzukEguBFI+gUsJoPfAd11d+5OL+87Trw7//M8z7mnYsOqlPS3sI8xPkJvEXCPY1zhFNtFwBuOsIwOHnCDl5zCDrq4Tuy+o7FO4QKvWKGJPh5xuQ6YRDsB/MQB7hDe/4Wu4gy3iZ1d9HCSA86xwHMChAEBOswBXxnVadxWNkMbswQK08PkoPBTf9daj0ANWxjFj/t1mAKduJV50bmkwBP2ym4xBYYYbAKU9WZDl0LfJKciEk/C95oAAAAASUVORK5CYII=[/img]