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

Integral and simplifying logarithms

OpenStudy (anonymous):

i need a min to type the equation

OpenStudy (anonymous):

k

OpenStudy (anonymous):

\[\int\limits_{0}^{1} (x+1) + \frac{ 1 }{ x-3 }+\frac{ 5 }{ x+2 }\]

OpenStudy (anonymous):

= \[\frac{ 1 }{ 2 } x^2 + x + \ln \left| x -3\right|+ 5\ln \left| x+2\right| \]

OpenStudy (anonymous):

from zero to one

OpenStudy (anonymous):

im sorrry i have no idea

OpenStudy (anonymous):

= \[(\frac{ 3 }{ 2 } +\ln \left| -2 \right|+5 \ln \left| 3 \right|)-(\frac{ 3 }{ 2 } + \ln \left| -3 \right|+5\ln \left| 2 \right|)\]

OpenStudy (anonymous):

this is where I get stuck. Can anyone help me simplify?

OpenStudy (anonymous):

i have no clue im srry

OpenStudy (misty1212):

HI

OpenStudy (misty1212):

what do you need, a number?

OpenStudy (misty1212):

it is a calculator exercise now, you will not compute this with pencil and paper

OpenStudy (phi):

your integral is ok: \[ \frac{ 1 }{ 2 } x^2 + x + \ln \left| x -3\right|+ 5\ln \left| x+2\right| \] at the upper limit, x=1 you get \[ \frac{ 1 }{ 2 } + 1 + \ln | 1-3| + 5 \ln | 1+2 | \\ = \frac{3}{2} + \ln 2 + 5 \ln 3 \] at the lower limit x=0 you get \[ 0 + 0 + \ln | -3| + 5 \ln|2| \\ = \ln 3 + 5 \ln 2 \] subtracting upper - lower: \[ \frac{3}{2} + \ln 2 + 5 \ln 3 - \ln 3 - 5 \ln 2 \\ = \frac{3}{2} + 4\ln 3 - 4 \ln 2 \] you can combine / re-write the logs using \[ \ln(a^b) = b \ln(a) \\ \ln \left(\frac{a}{b}\right) = \ln(a) - \ln(b) \] in other words: \[ \frac{3}{2} + 4\ln 3 - 4 \ln 2 \\ =\frac{3}{2} + \ln 3^4 - \ln 2^4 =\frac{3}{2} + \ln 81 - \ln 16\\ = \frac{3}{2} +\ln\frac{81}{16} \]

OpenStudy (anonymous):

it says the correct final is 3/2 - 4/5 ln 3/2

OpenStudy (anonymous):

\[\frac{ 3 }{ 2 }-\frac{ 4 }{ 5 }\ln \frac{ 2 }{ 3 }\]

OpenStudy (anonymous):

i got what you did Phi...it says i am wrong and showed me that answeer

OpenStudy (phi):

ok, we can do this \[ \frac{3}{2} + 4 \ln \frac{3}{2} \\= \frac{3}{2} - 4 \ln \frac{2}{3} \] but I don't see where the 1/5 comes from

OpenStudy (phi):

I would ask your teacher about this, because the answer does not match up with the question.

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!