całki
Pomocy: Mógłby mi ktoś pomóc?
a) ∫ (x
5+1)/(x(x−1)
2) dx
b) ∫ x/(1+x
3) dx
c)∫ 1/(√(1+x
2))
Proszę o rozwiązanie
6 wrz 00:01
Jack:
a) wymnoz mianownik i normalnie podziel wielomian
b)
Zauwaz, ze
x3 + 1 = (x + 1)(x2 − x + 1)
Nastepnie rozklad na ulamki proste
6 wrz 00:19
Jack:
c) na to jest gotowy wzor.
jedna z postaci to np. arsinh(x)
Oczywiscie mozesz policzyc samemu jakims podstawieniem tylko teraz nie widze zadnego prostego
6 wrz 00:32
Adamm: | x5+1 | | x5−2x4+x3+2x4−4x3+2x2+3x3−6x2+3x+4x2−3x+1 | |
| = |
| = |
| x3−2x2+x | | x3−2x2+x | |
| | 4x2−3x+1 | |
=x2+2x+3+ |
| |
| | x3−2x2+x | |
| 4x2−3x+1 | | A | | B | | C | |
| = |
| + |
| + |
| |
| x3−2x2+x | | x | | x−1 | | (x−1)2 | |
4x
2−3x+1=Ax
2−2Ax+A+Bx
2−Bx+Cx
A+B=4
−2A−B+C=−3
A=1
A=1, B=3, C=2
| 4x2−3x+1 | | 1 | | 3 | | 2 | |
| = |
| + |
| + |
| |
| x3−2x2+x | | x | | x−1 | | (x−1)2 | |
| | x5+1 | | 1 | | 3 | | 2 | |
∫ |
| dx=∫(x2+2x+3+ |
| + |
| + |
| )dx = |
| | x3−2x2+x | | x | | x−1 | | (x−1)2 | |
| | 1 | | 2 | |
= |
| x3+x2+3x+ln|x|+3ln|x−1|− |
| +c |
| | 3 | | x−1 | |
6 wrz 01:03
Adamm: | x | | A | | Bx+C | |
| = |
| + |
| |
| 1+x3 | | 1+x | | x2−x+1 | |
x=Ax
2−Ax+A+Bx
2+Cx+Bx+C
A+B=0
−A+C+B=1
A+C=0
A=−1/3, B=C=1/3
| x | | 1 | 1 | | 1 | x+1 | |
| =− |
|
| + |
|
| |
| 1+x3 | | 3 | 1+x | | 3 | x2−x+1 | |
| | 1 | 1 | | 1 | 2x−1 | | 1 | 1 | |
∫(− |
|
| + |
|
| + |
|
| )dx = |
| | 3 | 1+x | | 6 | x2−x+1 | | 2 | (x−1/2)2+3/4 | |
| | 1 | | 1 | | √3 | | 2x−1 | |
= − |
| ln|1+x|+ |
| ln|x2−x+1|+ |
| arctg( |
| )+c |
| | 3 | | 6 | | 3 | | √3 | |
6 wrz 01:16