<prompt> Ikiwa theta ni pembe kati ya vekta beginpmatrix 3 -4 endpmatrix na beginpmatrix 12 5 endpmatrix, kisha tafuta cos theta.  <response>: Tuna hiyoanzaaligncos theta fracanzapmatrix 3 -4 mwishopmatrix cdot anzapmatrix 12 5 mwishopmatrixleft anzapmatrix 3 -4 mwishopmmatrix kulia cdot kushoto anzapmatrix 12 5 mwishopmmatrix kulia frac3 cdot 12 -4 cdot 5sqrt32 -42 cdot sqrt122 52 frac36 - 205 cdot 13 frac1665.mwishopanga 