<prompt> Ikiwa mathbfa, mathbfb, na mathbfc ni vekta ambazo mathbfa cdot mathbfb -3, mathbf a cdot mathbfc 4, na mathbfb cdot mathbfc 6, kisha tafutamathbfb cdot 7 mathbfc - 2 mathbfa.  <response>: Hiyo inamaanisha naweza kuandika mathbfb cdot 7 mathbfc - 2 mathbfa kama 7 mathbfb cdot mathbfc - 2 mathbf b cdot mathbfa. Sasa ninaweza kuunganisha thamani zilizotolewa za bidhaa za nukta na kurahisisha. Ninapata 7 6 - 2 -3 42 6 48. 