Даны векторы a→2,2;-4{"color":"#202335","fontFamily":"stix","language":"ru"} и b→-1,25;-1.{"color":"#202335","fontFamily":"stix","language":"ru"} Найдите скалярное произведение векторов 3a→ {"color":"#202335","fontFamily":"stix","language":"ru"} и 4b→.{"color":"#202335","fontFamily":"stix","language":"ru"}