Mathematics
20 Online
OpenStudy (anonymous):
Can someone help me with this problem please
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
OpenStudy (anonymous):
can you help me
OpenStudy (loser66):
what do you think, give me your idea first, it's not a piece of cake
OpenStudy (anonymous):
um I think that we have to put the e^k where ever we see an x first
OpenStudy (loser66):
how about the "global minimum value of fx"?
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
yeah that is where I get confused with these problems
OpenStudy (loser66):
is it not the vertex of parabola? since it's is upward, so the minimum value is the vertex of it .
OpenStudy (anonymous):
ok
OpenStudy (anonymous):
so then 2
OpenStudy (anonymous):
ok
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
f'(x)=x+2xlnx
OpenStudy (loser66):
=0 when?
OpenStudy (anonymous):
?
OpenStudy (loser66):
is it right with the derivative?
OpenStudy (anonymous):
yes
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (loser66):
sorry, you are right,
OpenStudy (anonymous):
so then what?
OpenStudy (loser66):
and that derivative =0 to get the x value of the vertex,
OpenStudy (loser66):
=0 when?
OpenStudy (anonymous):
so then add 0 where there is an x
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (loser66):
no, it =0 when x(1+2lnx)=0 iff x =0 or 2lnx =-1 (reject)
OpenStudy (anonymous):
oh ok
OpenStudy (loser66):
sorry, not that, not reject, reject x =0
OpenStudy (loser66):
accept the value of 2lnx = -1 ---> lnx = -1/2 ---> x = e^-1/2
OpenStudy (loser66):
combine with yours x = e^k ----> k = 1/2
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (loser66):
got it?
OpenStudy (anonymous):
yes
OpenStudy (loser66):
ohoh -1/2
OpenStudy (anonymous):
why -.5
OpenStudy (loser66):
sorry, so tired , really got?
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (loser66):
yeap
OpenStudy (anonymous):
so then -.5 is the final answer
OpenStudy (loser66):
yeap
OpenStudy (loser66):
I think so. if not, I hand off,
OpenStudy (anonymous):
thanks