Question

help with calclulus

Answer 1

can you explain to me what was done?
I undertsnad what they did with the infinity but I dont get how they added a 2 to the integrand

Answer 2

if you look at the intergrand they have put 1/2 out the front and the numerator is 2y...... remember 1/2 x 2y = y.....

Answer 3

LOL but why didthey do that?

Answer 4

sorry abt the attachment but there seems to be a bug

Answer 5

its to make the numerator look like the derivative of the denominator.... which would suggest the solution would be a ln function

Answer 6

the solution might be... let u = y^2 du = 2y

\[1/2\int\limits_{0}^{b} du/(u^2 + 1)\]

which is tan^(-1)

Answer 7

oops should read 1/2 tan^(-1) (u) then re substitute 1/2 tan^(-1) (y^2)

Answer 8

Thanks that was clear campbell :D That is exactly what I wanted to know