Производная обращается в 0 при x=1 или x=3.
1. 80 : 8 = (40+40) : 8 = 40:8 + 40:8 = 5+5 = 10
2. 96:8 = (80+16) : 8 = 80:8 + 16:8 = 10 + 2 = 12
3. 90:9 = (45 + 45): 9 = 45:9 + 45:9 = 5+5= 10
4. 84: 7 = (42+42) : 7 = 42:7 + 42:7 = 6+ 6= 12
5. 70 : 7 = (35+35) : 7 = 35:7 + 35:7 = 5 + 5 = 10
6. 84:6 = (42+42):6 = 42:6 + 42:6 = 7 + 7 = 14
7. 50:5 = (25 +25):5 = 25:5 + 25:5 = 5 + 5 = 10
8. 85:5 = (50 = 35):5 = 50:5 + 35:5 = 10 + 7 = 17
9. 60:6 = (30 + 30):6= 30:6 + 30:6 = 5 + 5 = 10
10. 117 : 9 = (63 + 54):9 = 63:9 + 54:9 = 7 + 6 = 13
а) sin(x-?/3) = -1/2
x-?/3 = -?/6 + 2kn или x - ?/6= 7π/6 + 2kn
х = ?/6 + 2kn х = 8π/6 + 2kn
b) tg(3x+?/6)=1
3x+?/6 = ?/4 + кн
3x = 3π/12-2π/12 +кн
3x = ?/12 + kn
x= ?/36 + kn/3
c) sin(4x+?/2) =1
4x+?/2 = ?/2 + 2kn
4x=2kn
x= kn/2
d) ctg(2x-?/3) = - √3
2x - ?/3 = -?/6 + кн
2x = -?/6+2 π/6 + кн
2x = ?/6 + kn
x = ?/12 + kn/2
1) 124, 146, 150, 200, 208, 260
2) 150, 175, 200, 215, 260
3) 150, 200, 260
Х-2у=7
5х+4у=7
х=7+2у
5(7+2у)+4у=7
35+10у+4у=7
14у=-28
у=-2
х=7-4=3
<em>х*у=-6</em>