Find the area of the region bounded by y = 9 / (25 − x^2) and y = 1.
help, please?
I have gotten the same answer as wolfram alpha, and I don't know what is wrong
\[x + 9/10 \ln(5-x) - 9/10\ln(x+5) \]
our bounds are from -4 to 4 right?
i don't have bounds for this question.
you do have bounds; you just got to determine their value; they are where the lines cross
wait, what do you mean?
oh... I need to put the bounds into the equation and solve for an number as the answer
we can do this simpler by taking the bounds from 0 to 4 and doubling it since they are equal on both sides of the y axis
the area of 4 wide and 1 tall rectangle formed by y=1 and x=4 is an area of 4 :) now subtract away that area under the 9/(25-x^2)
4-9/10(ln(9))
if the integration is good; then yes; now double it to get both areas on the left and right of the yaxis
multiply by 2....4 - 9/5(ln(9))? but is says it is wrong...
\[\int\frac{1}{a^2-x^2}dx\implies\ \frac{1}{2a}\ ln\left|\frac{a+x}{a-x}\right|\]
a=5; x=x in this case; then bring back the 9 right?
yep
let me right it again in the system....this is right
\[\frac{9}{10}ln\left|\frac{5-4}{5+4}\right|-\frac{9}{10}ln\left|\frac{5}{5}\right|\]
\[2\ [\ 4-\frac{9}{10}\left(ln(1/9)\right)]\] is what I get if I did it right :)
how did you get 9 on the bottom?
a = 5; and x=4 it the bounds... just plugged it in
and I got it upside down too lol
oh...fraction of ln
wait.....ln|9| - ln|1| = 1/9?
\[8 - \frac{9\ ln(9)}{5}\]
i had my 5+x and my 5-x transposed
oh...kay....now it is right. What I didn't do is multiply 4 *2, I just divided by 2
yeah you did, but you got it right. thanks for the help!
youre welcome :)
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