| 1 | x2 | x2lnx | x2 | |||||
∫ xlnxdx = [ u = lnx; u' = | ; v = x; ∫v = | ] = | − ∫ | dx = | ||||
| x | 2 | 2 | 2 |
| x2lnx | 1 | x2 | 1 | 1 | ||||||
− | ∫ x2 = | − | * | x3 + C | ||||||
| 2 | 2 | lnx | 2 | 3 |
| x2ln | x2 | |||
W odpowiedziach do zadania stoi : | − | + C. Gdzie zrobiłem błąd? | ||
| 2 | 4 |
| 1 | x2 | x | ||||
u'*v = | * | = | ![]() | |||
| x | 2 | 2 |
| 1 | ||
zgubiłeś | ||
| x |
| x | ||
albo aby oznaczenia się zgadzały ... u'*∫v = | ||
| 2 |
| 1 | x2 | |||
lnx=u; v'=x ; to | dx=du; v=∫xdx= | ] | ||
| x | 2 |
| x2 | x2 | 1 | x2 | x | ||||||
=lnx* | −∫ | * | dx= | lnx−∫ | dx= | |||||
| 2 | 2 | x | 2 | 2 |
| x2 | x2 | |||
= | lnx− | l+C | ||
| 2 | 4 |
.