I'm on the last problem of a maple assignment. Maple can't integrate this function. I'm trying to figure out what to substitute so that I can simplify the function into something that maple can integrate. The xlnx part is what's messing me up.
int (1+ln(x))sqrt(1+(xlnx)^2) dx
I don't need anyone to evaluate it, I just need some help figuring out what to substitute. Maple can do the rest.
int (1+ln(x))sqrt(1+(xlnx)^2) dx
I don't need anyone to evaluate it, I just need some help figuring out what to substitute. Maple can do the rest.
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Note :
∫ √(a²+u²) du = (1/2) { u·√(a²+u²) + ln | u + √(a²+u²) | } + C ... (1)
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Let : I = ∫ √[ 1 + (x· ln x)² ] • ( 1 + ln x ) dx .................. (2)
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Put : u = x· ln x
Then, by Quotient Rule,
du/dx = x·( 1/x ) + (ln x)· (1)
du/dx = 1 + ln x
( 1 + ln x ) dx = du .................................. (3)
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Using (3) in (2),
I = ∫ √(a²+u²) du.
Now Use (1).
Finally, back-substitute x·ln x for u.
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∫ √(a²+u²) du = (1/2) { u·√(a²+u²) + ln | u + √(a²+u²) | } + C ... (1)
________________________________
Let : I = ∫ √[ 1 + (x· ln x)² ] • ( 1 + ln x ) dx .................. (2)
________________________________
Put : u = x· ln x
Then, by Quotient Rule,
du/dx = x·( 1/x ) + (ln x)· (1)
du/dx = 1 + ln x
( 1 + ln x ) dx = du .................................. (3)
_____________________________
Using (3) in (2),
I = ∫ √(a²+u²) du.
Now Use (1).
Finally, back-substitute x·ln x for u.
_____________________________
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Sorry,
I should have said : Product Rule.
I should have said : Product Rule.
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