5
, ; . , , .
2.1. , , , .
3.1., , .
3.2. .
3.3. (. 5).
: () , () .
[1].
1. f(x) , f (x)>0 [a, x] f (x)<0 [x, b], f(x).
2. f(x) , f (x)<0 [a, x] f (x)>0 [x, b], f(x).
1. .
2. .
3. [2].
4. , .
5. , .
6. .
1. .
2. , (; b).
3. [; b].
4. .
: xo , y = f(x) :
k=f (xo)=tg (6.1)
f(x) :
(6.2)
: , ; , :
v(t0)=x'(t0) (6.3)
a(t0)=v'(t0)= x''(t0) (6.4)
1. y=x3+6x2+9x .
1) D(y)=R
2) : y=(x3+6x2+9x)=3x2+12x+9
|
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3) : y=0, ..
3x2+12x+9=0
, : x1=-1 x2=-3.
4) :
+ - +
-3 -1
()
x=-4, y=3*16-48+9=9>0
x=-2, y=12-24+9=-3<0
x=0, y=0+0+9=9>0
5) :
xmin=-1, xmax=-3.
6) :
ymin=y(-1)=-1+6-9=-4, ymax=y(-3)=-27+54-27=0.
7) .
2. y= .
1) : D(y)=R\{2}; x=2 .
2) : y= .
3) :
x2-4x=0 x(x-4)=0 x=0, x=4
y=0, <=>
(x-2)2≠ 0 x≠ 2
4) :
+ - - +
() 0 2 4
x=-1, y=(1+4)/9=5/9>0
x=1, y=(1-4)/1=-3<0
x=3, y=(9-12)/1=-3<0
x=5, y=(25-20)/9=5/9>0
5) : xmin=4, xmax=0.
6) :
ymin=y(4)=16/2=8, ymax=y(0)=0
7) .
3. y = x 3 12 x + 7 [ 3, 0].
.1) : y/ = 3 x 2 12, 3(x 2 4) = 0.
, = 2.
2) ( 2) = 23.
3) : ( 3) = 16 (0) = 7.
4) ( 2) = 23, (0) = 7.
: . ( 2) = 23, . (0) = 7 [ 3, 0].
4. , - ,- , . ( ) 3 /?
. , , to.
: .
, 3 /, to 3.
:
: 8.
5. 8 . 80 50 . , .
. . 0<x<25.
:
V = x (80-) (50 2) = 4³ - 260² + 4000.
V´ = 12² - 520 + 4000 = 0,
1 = 100:3 = 33 , 2= 10.
1- . 2= 10 , 80 20 = 60 , 50 20 = 30 .
V = 10 · 60 · 30 = 18000(³).
: 10, 30 60.
1. :
) (. 6);
) .
.
2. (. 6).
3. . ?
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|
4. , 50?
7. , ,
S=19,6t 4,9t2. . S- (), t- ().
6
. | . | |||||
=(-3)2(-2) | [1;4] | = | [-2;5] | |||
= 3+2 | [-4;1] | = - 4+22+3 | [-0,5;2] | |||
= 3-2-3 | [-2;6] | = 24- | [-2;2] | |||
= - 4+22+1 | [-3;3] | =-3+92-24+10 | [0;3] | |||
= 4-82-9 | [-3;3] | =5-54+53+1 | [-10;10] | |||
=(-2)(+1)2 | [-1,5;1,5] | =3-32+9+35 | [-4;4] | |||
= - 3+2 - | [-1,5;1,5] | =3-3 | [-0,5;0,5] | |||
=35-54+4 | [-1;1] | =4-82-9 | [0;3] | |||
=92-93 | [-0,5;1] | =4-82-9 | [-1;1] | |||
= 3-4 | [-3;3] | =3+32-9 | [-4;0] | |||
=24- | [-1;1] | =3+32-9 | [2;4] | |||
= 2 - | [-3;-0,5] | =23-92+12-3 | [0;3] | |||
= | [-1;2] | = | [1;3] | |||
=3-3 | [-1,5;1,5] | = | [-10;10] | |||
=22-4 | [-2;1,5] | =23-92+12-8 | [0;5] | |||
= - 2 | [-8;8] | =23-32-12+8 | [0;5] | |||
= - | [-8;8] | = 3-2-3+ | [-1;3] | |||
= 3-1,52-6+4 | [-2;3] | =3-62+9-3 | [-1;3] |
6.1. .., .. , 55, 56.
6.2. .. , 9.9. 9.10.
[1] 0 - () .
f(0) () .
[2] , .