i dont know why i'm having so much problem finding a appropriate trigonometric sub for x. I can do the rest fine as long as i can find the right sub. please help me with the right trig. sub for this problem:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\int x*sqrt(6x^2-36x+49)dx[/tex]

here's what i done:

[tex]\int 6x*sqrt(x^2-6x+\frac{49}{6})[/tex]

then i did complete the square...

[tex]\int 6x* sqrt((x-3)^2 -5/6)[/tex]

so i came up with x = sqrt(5/6)*sec(t) as my trig. sub, but it's incorrect. can someone lend me a hand?

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# Homework Help: Another trig. sub

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