<span>1)-2х²+3х-4=-х²-х+(2-х²),
-2х</span>²+3х-4=-х²-х+2-х²,
-2х²+3х-4=-2х²-х+2,
-3х-4=-х+2,
3х+х=2+4,
4х=6,
х=6:4,
х=1,5.
Ответ: 1,5.
<span>(5-4а)(5+4а)=25-16а²
</span>(5-4а)(5+4а)=5²-(4а)²=25-16а²
25-16а²=25-16а²
Доказано.
(a-x)(a+x)(a²+x²)=(a²-x²)(a²+x²)=a⁴-b⁴
По формуле: sin(15-45)=sin(-30)=-0,5
5*2/7+5,4=37/7+5,4=37+37,8/7=10,68
8 - 6(2x - 1/2) + 12x - 2 = 8 - 12x + 3 + 12x - 2 = 9