2x+x=-20
3x= -20
2
x = - 6 __
3
Нули функции
2(x + 1)^2 - 8 = 0
2(x + 1)^2 = 8
(x + 1)^2 = 4
(x + 1)^2 - 2^2 = 0
(x + 1 - 2)(x + 1 + 2) = 0
(x + 3)(x - 1) = 0
x + 3 = 0
x = - 3
x - 1 = 0
x = 1
( - 3; 0) ; ( 1; 0)
========================================
y = 2(x + 1)^2 - 8 = 2(x^2 + 2x + 1) - 8 = 2x^2 + 4x - 6
x0 = - b/2a = - 4/4 = - 1
y0 = - 8
( - 1; - 8) - вершина
183.
a)
решений нет
б)
или
184.
+ - +
____________ -9 ____________________ 1 _________________
+ _ +
________________ -1 _______________ 3 _____________________
1. 5,4*0,8+0,08=4,32+0,08=4,4
2. 10*1/5²-12*1/5=10/25-12/5=-2
3. 21/49-10/7=-1
4. 17/8-11/20=63/40 63/40:5/46=14,49
5. -0,6*(-9)*4=35,4 1,9*81=153,9 35,4+153,9-4=185,3
6. 4,1+5,3=9,4 9,4/9,4=1
7. 3/22+2/11=7/22 7/22:5/33=2,1
8. 12/60=1/5=0,2
9. 6/9-14/3=-4
10. -0,7*1000=-700 -90-700=-790