(0,3а-1,2b)+(a-b)-(1,3a-0,2b)

(0,3а - 1.2b)+(a-b) - (1.3a - 0.2b)=0.3a-1.2b+a-b-1.3a+0.2b= - 2b 3)   ...........=11p³-2p²-p³+p²-5p²-3p³=7p³ - 6p² 4)   ..........=5x²+6x³+x³-x²+2x³-4x²=9x² 1)..........= - 2x³+xy²+x²y-1+x²y - xy²+3x³= x³ +2x²y - 1 2)..........=3x²+5xy+7x²y - 5xy - 3x² - 7x²y+3x²= 3x²  3)..........=8a² - 10ab -b²-6a²+2ab-b² - a² +8ab -4b²= - 6b² 4).........=4a² - 2ab -b² +a²-b² +2ab+3a²+b²-ab=8a² - ab - b²