I have some struggle to find sound solutions for these integrals.
It would give me much easier to comprehend what I have done wrong.
Thank you in advance.
Best regards
Anhard
Example 1
Example 2
Example 3
Example 4
Can use the substitution x= a tan(theta) or x= a sin(theta)
I can do #2 if that helps, not sure about the others. I used u=3x and the D I method and got 1/9*(sin(u)-ucos(u))-2/3*cos(u)+c
Which is
Thank you Phinehas. I think I forgot to substitute it frist. I will rewatch this example.
#4 Use x=3sin(theta).
dx=3cos(theta) dtheta.
Substituting back:
sin(theta)=x/3
tan(theta)=x/sqrt(9-x^2)
Don't understand what you're saying about integration by parts, if you do that u-sub you're done at least when I did it. The answer is 5/9*(sin(10)-sin(7))
my answer to number 3
By the way what did u do wrong for that one