$\mathop A\limits^ \to  $ અને $\mathop B\limits^ \to  $ વચ્ચેનો ખૂણો $ =110^0 – 20^0 = 90^0 $ 

$R\,\, = \,\,\sqrt {{A^2}\,\, + \;\,{B^2}\,\, + \;\,2AB\,\cos \,\,90^\circ } \,\, = \,\,\sqrt {{5^2}\,\, + \;\,{{12}^2}} \,\, = \,\,13m$

સદીશ $\mathop A\limits^ \to  $ માથી $\mathop R\limits^ \to  $ નો ખૂણો $\alpha $ છે તેમ લો.

$\tan \,\,\alpha \,\, = \,\,\frac{{B\,\,\sin \,\,\theta }}{{A\,\, + \;\,B\,\,\cos \,\,\theta }}\,\, = \,\,\frac{{12\,\,\sin \,\,90^\circ }}{{5\,\, + \;\,12\,\,\cos \,\,90^\circ }}\,\, = \,\,\frac{{12\,\, \times \,\,1}}{{5\,\, + \;\,12\,\, \times \,\,0}}\,\, = \,\,\frac{{12}}{5}$

અથવા $\alpha \,\, = \,\,{\text{ta}}{{\text{n}}^{{\text{ – 1}}}}\,\,\left( {\frac{{12}}{5}} \right)\,$ સદીશ $\mathop A\limits^ \to  $ અથવા $\left( {\alpha \,\, + \;\,20^\circ } \right)\,X\,$ અક્ષ સાથે