Решите уравнения: 1. x^2=8x-17 2. 14x=-49-x^2 3. 36+17x=-2x^2 4. 7x^2-3x=4 5.6x=9x^2=-1 6. 0.81-x^2=0 7. 5x+9x^2=0 8.1+2x=8x^2 9. 19x-6x^2-10=0 10. 8+2x^2=0 11. 40x-25-16x^2=0 12. -36-x^2=-12x
269
335
Ответы на вопрос:
x^2-8x+17=0 => d=64-4*17 = р н
4x=-49-x^2 => x^2+4x+49=0 => d=16-4*49=р н
36+17x=2x^2 => 2x^2+17x+36=0 => d=289-288=1 => x1=-9/2 => x2=-4
7x^2-3x=4 = > d9-4*7*(-4)=121 => x1=1 => x2=-9/14
x^2=81 = > x=+-9
5x+9x^2=0 => x(5+9x)=0 => x=0 или x=-5/9
1+2x=8x^2 => 8x^2-2x-1=0 => d=4-4*8*(-1)=36 => x1=1/2 => x2=-1/4
19x-6x^2-10=0 => 6x^2-19x+10=0 => d=361-4*6*10=121 => x1=30/38 => x2=8/38
8+2x^2=0 => 2x^2=-8 => x^2=-4 => x=р н
40x-25x^2+12x=0 => 28-25x^2=0 => x(28-25x)=0 => x=0 или 25x=28 => x=28/25
используем два выражения
a³+b³=(a+b)(a²-ab+b²)
(a-b)²=a²-2ab+b²
(67^3+52^3) / 119-67 * 52 =(67+52)(67^2-67*52+52^2)/119 - 67*52= 119*(67^2-67*52+ 52^2)/119-67*52= 67^2-2*67*52+52^2=(67-52)^2=15^2=225
Популярно: Алгебра
-
masha00700919.10.2022 01:47
-
KoRiiZa02.07.2022 07:55
-
Polia11111123.07.2022 05:05
-
BOJl40K26.01.2020 00:06
-
MyNameIsLiza12304.04.2023 12:08
-
elenavalkova9205.05.2023 10:14
-
aajlarov04.06.2020 07:46
-
рената123930520.10.2021 15:01
-
SeverBig3614.07.2022 14:10
-
anzhela3316.12.2021 13:55