What is a suitable substitution for this integration problem?

[delsoo]

Homework Statement

for this question, the question only stated SUITABLE substituition, what substituition should i use? this substituion does not involve trigo functions , am i right? P/S : I'm just asking opinion, not the full working.

Homework Equations

The Attempt at a Solution

 

[Dick]

Homework Statement

for this question, the question only stated SUITABLE substituition, what substituition should i use? this substituion does not involve trigo functions , am i right? P/S : I'm just asking opinion, not the full working.

Homework Equations

The Attempt at a Solution

No, you don't need trig functions. Use a substitution that will get rid of the square root.

 

[delsoo]

what should i sub? how to determine the substitution for this type of question? can i sub u= surd x ? or u=( 1+ surd x ) ? or u=(( 1+ surd x ) sqrt)

 

[Curious3141]

what should i sub? how to determine the substitution for this type of question? can i sub u= surd x ? or u=( 1+ surd x ) ? or u=(( 1+ surd x ) sqrt)

Why don't you try it and see? Both $u = \sqrt{x}$ and $u = 1 + \sqrt{x}$ work but one gives a quicker and neater answer.

 

[delsoo]

for this type of question, can i use any substituition i like such as u=(1+ surd x )^2 ?

 

[Dick]

for this type of question, can i use any substituition i like such as u=(1+ surd x )^2 ?

You can TRY any substitution you like, they won't all help you to integrate. Don't forget when you substitute u=f(x) you also have to find du so you can figure out how to express the dx part in terms of u.