Jawabanmu

2014-09-03T15:12:22+07:00
1.(3x²+2x-1) + (x²-5x+6) = 
 =3x² + 2x - 1 + x² - 5x + 6 
 =3x² + x² + 2x - 5x - 1 + 6
 = 4x² - 3x + 5

2.2(x+2y-xy) + 5(2x-3y+5xy) = 
 = 2x + 4y - 2xy + 10x - 15y + 25xy
 = 2x + 10x + 4y - 15y - 2xy + 25 xy
 = 12x - 11y + 23xy

3.3p³-2pq²+p²q-7p³+2p²q =
 =3p³ - 7p³ + p²q + 2p²q - 2pq²
 = -4p³ +3p²q - 2pq²

4.-2(p³-2pq+q²) + 3(p³+4pq-q²)
 = -2p³ + 2pq - 2q² + 3p³ + 12pq - 3q²
 = -2p³ + 3p³ + 2pq + 12pq - 2q² - 3q²
 = p³ + 14pq - 5q²