Thread: Integration by substitution

Hi there. I'm new here :-)

I've been going through a fair few substitution questions, but I have been stumped on this one.

I have to solve the following by substitution:


Now normally I find these questions relatively easy, where all the values under the square root are substituted for u.

This question does not seem to work the same way since or

Clearly this will not replace the term outside the square root.


Any ideas? :-)

Originally Posted by fityfity

Hi there. I'm new here :-)

I've been going through a fair few substitution questions, but I have been stumped on this one.

I have to solve the following by substitution:


Now normally I find these questions relatively easy, where all the values under the square root are substituted for u.

Yes, exactly right. Let

This question does not seem to work the same way since or

Yes, and .

Clearly this will not replace the term outside the square root.


Any ideas? :-)

Ahh that makes so much sense

It always appears easy once someone shows you

Thank you very much for your help