1)
2) (1)
3)
4) ,
33. .
R(sinx, cosx)dx
tg(x/2)=t, sinx = 2t/(1+t2), cosx = (1-t2)/(1+t2), dx = 2dt/(1+t2)
R(sinx, cosx)dx
tgx=t, sinx = t/( 1+t2), cosx = 1/( 1+t2), dx = dt/(1+t2)
R(sinx)cosxdx
sinx=t, cosxdx = dt
Sin2mxcos2nxdx
cos2x = (1+cos2x)/2, sin2x = (1-cos2x)/2, sinxcosx = 1/2sin2x
Sinmxcosnxdx
n=2k+1, (cos2x)k , sinx = t
6)∫sinαx sinβx = ½(cos(α-β)x cos(α+β)x;
∫cosαx cosβx = ½(cos(α-β)x + cos(α+β)x;
∫ sinαx cosβx = ½(sin (α-β)x + cos(α+β)x
34. .
1) ∫R(x, (ax+b/cx+d)r1/s1)dx
ax+b/cx+d = tN, N
2) ∫R(x, ( a2-x2)dx, a = sint
3) ∫R(x, ( a2+x2)dx, a = tgt
4) ∫R(x, ( x2-a2)dx, a = a/cost
5) : xm(axn+b)pdx
1) p
2) m+1 , axn+b=ts, p=r/s
3) m+1/n+p , axn+b=tsxn,
6) R(x, ( ax2+bx+c)
1) >0, ax2+bx+c = t+-.
2) <0, ax2+bx+c = xt+-. c
3) ax2+bx+c 1 2, ax2+bx+c = t(x-x1)
35. . . . , . , 1- .
. S=Vt ( ). . ∆t . V(t) ≈ V(t0).
∆S=S(t0+ ∆t)-S(t0). [t0; t] n : [t0; t1] .
∆k = tk-tk-1. : S(t)-S(t0) = ∆S ≈ V(T1)(t1-t0) + V(T2)(t2-t1)
.., max ∆kà0, D Eà∆S
. f(x) [a; b] I , ε>0 δ>0 , |I- δ |< ε , λ (P; ξ)< δ. [a;b], I .
.
.
1) f(x) [a; b]. c f(x) [a; b]: ∫Cf(x)dx = C∫f(x)dx
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2) f(x) g(x) [a; b]. f(x)+g(x) . [a; b]:
∫(f(x)+-g(x))dx = ∫f(x)dx +- ∫g(x)dx
3) ∫(1f1(x)+C2f2(x)+c3f3(x))dx = C1∫f1(x) + C2∫f2(x) + C3∫f3(x)
4) ∫f(x)dx = -∫f(x)dx,
5) ∫f(x)dx (a;b) = ∫f(x)dx (a; c) + ∫f(x)dx (c; b)
6) ∫|f(x)dx| <= ∫|f(x)|dx
7) f(x) <= g(x), (- [a; b], f(x), g(x) , : ∫f(x)dx <= ∫g(x)dx
8) f(x) [a; b] m <= f(x) <= M, x(-[a; b]. m(b-a) <= ∫f(x)dx <= M(b-a)
. f(x) [a; b], ξ (- [a; b] :
f(ξ) = ∫f(x)dx / (b-a)
36. . .
. f(x) > 0, . [a; b].
,
y = 0, x = a, x = b, y = f (x)
AB n ( x1, x2 ). ξ. f(ξ1)*∆x1 + . S. , .
Sabcd = ∫f(x)dx, .