Ask your own question, for FREE!
Mathematics 18 Online
OpenStudy (anonymous):

can someone check and see if this is right?

OpenStudy (anonymous):

\[\int\limits_{?}^{?}(1+4x)/(\sqrt{1+x+2x ^{2}}dx\]

OpenStudy (anonymous):

i got \[.5\ln \left| \sqrt{1+x+2x ^{2}} \right| +c\]

OpenStudy (rogue):

\[u = 1 + x + 2x^2, du = (1 + 4x) dx\]

OpenStudy (anonymous):

it looks wrong

OpenStudy (rogue):

There is no log. Instead it is \[2 \sqrt{ 1 + x +2x^2}\]

OpenStudy (anonymous):

why could you not use ln

OpenStudy (rogue):

well, the integral becomes \[\int\limits_{}^{} \frac {du}{u^.5}\]

OpenStudy (rogue):

\[\int\limits_{}^{} = u^{-.5}du\]

OpenStudy (anonymous):

\[\int\limits \frac{f'(x)}{f(x)}dx=lnf(x)\]

OpenStudy (rogue):

oops. There isn't supposed to be an equal sign in the integral.

OpenStudy (anonymous):

ok i think i got it

OpenStudy (rogue):

Alright, just the use power rule for integration to solve.

OpenStudy (anonymous):

thanks

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!