A community for students.
Here's the question you clicked on:
 0 viewing
y2o2
 3 years ago
Solve it ... if you can :)
f(x) + f´(x) = x³ + 5x² + 2
y2o2
 3 years ago
Solve it ... if you can :) f(x) + f´(x) = x³ + 5x² + 2

This Question is Closed

dumbcow
 3 years ago
Best ResponseYou've already chosen the best response.1\[\large f(x) = x^{3}+2x^{2}4x+6+Ce^{x}\]

y2o2
 3 years ago
Best ResponseYou've already chosen the best response.0Nope, that's not the answer , and don't try integration.

dumbcow
 3 years ago
Best ResponseYou've already chosen the best response.1really, oh ok i just solved it like it was a linear ODE

dumbcow
 3 years ago
Best ResponseYou've already chosen the best response.1actually it is right http://www.wolframalpha.com/input/?i=y%27+%2By+%3D+x^3+%2B5x^2%2B2

y2o2
 3 years ago
Best ResponseYou've already chosen the best response.0No , it's not . the function doesn't contain any unknown but "x".

dumbcow
 3 years ago
Best ResponseYou've already chosen the best response.1? C is just a constant, you have to provide an initial value or a point to get a particular solution

y2o2
 3 years ago
Best ResponseYou've already chosen the best response.0f(x) + f´(x) = x³ + 5x² + 2 so x³ + 5x² + 2 is the function plus its derivative so you you have to extract from x³ + 5x² + 2 a function and it's derivative x³ is the highest power , so it must belong to f(x) so f(x) = x³ +... and f´(x) = 3x²+... so f(x) = x³ + 2x²+... , so that 2x² + 3x² = 5x²+... and f´(x) = 3x² + 4x+... so f(x) = x³ + 2x²  4x+... , so that 4x+4x =0 f´(x) = 3x² + 4x4 f(x) = x³ + 2x²  4x + 6 so that 4+6 = 2 f(x) + f´(x) = (x³+2x²4x+6 )+ (3x²+4x4) = x³+5x²+2

dumbcow
 3 years ago
Best ResponseYou've already chosen the best response.1oh i see you solved it intuitively, well we are both correct if i make C=0 your answer is only 1 of many possible solutions to the differential equation
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.