Stuck yet again... trig integral substitution completing the square. I only need to say what needs to be substituted for x, so it doesn't need to be solved.

Question

anonymous · Answer

attachment

anonymous · Answer

the computer says that my answer is wrong :/ It wants x=f(theta)

perl · Answer

do you have link to computer

anonymous · Answer

well... I can't really post a link, but I took a screen shot...

perl · Answer

still want help?>

anonymous · Answer

yes please :/. If you can, I would be very grateful :p

perl · Answer

so I got integral sqrt(5) *x sqrt ( (x+3)^2 - 3/5 )

perl · Answer

we want integral sqrt( u^2 - a^2) , substitution u = a sec theta

perl · Answer

so you have the option of first doing u substitution

perl · Answer

or you can do  x + 3 = sqrt(3/5) sec theta

anonymous · Answer

Thank you perl. You are a lifesaver :)

perl · Answer

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