1. р(х) = 2(-3х²+2)+(1-х)-(х²-4х) = -6х²+4+1-х-х²+4х = -7х²+3х+5
2. а) 3/4 m²n²(4m - 8n - 4/3 mn) = 3/4 m²n² * 4m - 3/4 m²n² * 8n - 3/4 m²n² * 4/3 mn = 3m³n²-6m²n³-m³n³ = -m³n³+3m³n²-6m²n³
б) (2m+1)(4-m) = 8m-2m²+4-m = -2m²+7m+4
в) (25m²n-30mn²) : (-5mn) = 5mn(5m-6n) / -5mn = -(5m-6n) = -5m+6n
3. (3х+4)(4-3х)-(2х+1)² = 16-9х²-4х²-4х-1 = -13х²-4х+15
4. х-первое число, х+7 - второе, х+14 - третье
х(х+14)-х(х+7)=56
х²+14х-х²-7х=56
7х=56
х= 8 - первое число
8+7 = 15 - второе число
8+14 = 22 - третье число
5. 3(1-2у)(1+2у+4у²)+4(6у³-1) = 3(1-8у³)+4(6у³-1) = 3-24у³+24у³-4 = -1