: .
.
. , , , .
: f(x), f(x)
: f(x), f(x)
. f(x) . F(x), f(x)
F(x) = f(x) (1) dF(x) = f(x) dx (2)
d () , F(x) . , F(x) F(x), , . .
. F(x) = 2x2 f(x) = 4x. ,
F(x) = (2x2) = 4x = f(x). 2x2 + 6, 2x2 + 8, 2x2 + const 4. : .
. f(x) . dF(x) = f(x) dx = F(x) + C (3)
d . f(x) , f(x) dx - , x - , - , C - .
y = F(x) . . , .
, .
.
, .
1. xn dx = + C (n ¹ -1); 2. = ln |x| + C; 3. ex dx = ex + C;
4. ax dx = + C; 5. cos x dx = sin x + C; 6. sin x dx = - cos x + C;
7. = tg x + C; 8. = - ctg x + C; 9. tg x dx = - ln|cos x|+ C;
10. ctg x dx = ln|sin x| + C; 11. = arcsin x/a + C = - arccos x/a + C;
12. = ln|x+ | + C; 13. = (1/a) arctg x/a + C;
.
10. ( f(x) dx) = f(x), .. (F(x) + C) = F(x) = f(x)
.
20. d ( f(x) dx) = ( f(x) dx)dx = f(x) dx
30. d F(x) = F(x) dx = f(x) dx = F(x) + C
.
40. a f(x) dx = a f(x) dx, .. d (a F(x)) = a dF(x)
.
50. [f(x) + g(x)] dx = f(x) dx + g(x) dx, .. .
.
60. : u=u(x), ..
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f(x) dx = F(x) + C (), f(u(x)) du(x) = F(u(x)) + C ().
-. u(x) F(x). F(u(x)). Ÿ :
d [F(u(x))] = F`x dx = F`udu, .. dF dx, du. dF(u) = F`udu (): f(u) du = F(u) + C. . u(x). .
. esin x cos x dx = esin x d(sin x) = eu du = eu + C = esin x + C, (u = sin x)
.
, , dx = 1/a d(ax + b),
x2 dx = 1/3 d(x3), cos 2x dx = d(sin 2x /2), 1/x dx = d(ln x). . .
(3x2 cos x + 6 /x)dx = 3 x2 dx - cos x dx + 6 dx/x = x3 sin x + 6 ln x + C
= = 2(3/8)x8/3 - 3 x-3/(-3) + 5 ln x + C
cos 2x dx = d (sin 2x / 2) = (sin 2x / 2) + C
. tg2x dx, , , 2x(1 + 3 x2 2-x) dx
.
f(x) , t, x = g(t), t = g-1(x) h(x),
f(x) dx = f[g(t)] g(t) dt = F(t) + C = F(h(x)) + C
t . t = h(x) .
. esin x cos x dx = { t = sin x, dt = (sin x)dx = cos x dx} =
= etdt = et + C = esin x + C. : (esin x + C)` = esin x cos x
. .
: t = ax + b. . e3x dx, , sin (a b x) dx
: f(x) dx = F(x) + C, f(ax + b) dx = (1/a) F(ax + b) + C, (4)
- u(x) dx du(x) (5)
. , , ,
f(x) = u`(x)/u(x). dx = ln u(x) + C (6)
, .
. x dx /(x2 + 1) = ½ d(x2 + 1) / (x2 + 1) = ½ ln |x2 + 1| + C
tg x dx, ctg x dx, ,
.
u = u(x), v = v(x) - , d(uv) = udv + vdu.
.
u dv = uv + v du (7)
u dv v du.
:
f(x) = P(x)A(x), P(x) = a xn + b xn-1 +...+ c, A(x) - .
A(x) = ekx, ax, sin kx, cos kx, u = P(x), dv = A(x) dx
A(x) = loga x, arcsin x, arccos x, arctg x, arcctg x, u = A(x), dv = P(x) dx
. x cos x dx = {u = x, du = dx, dv = cos x dx, v = sin x} = x sin x - sin x dx =
= x sin x + cos x + C. : (x sin x + cos x + C)` = x cos x
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