integration help Watch

01blowenm
Badges: 0
#1
Report Thread starter 9 years ago
#1
can someone please help me

how do u integrate
(5x+2).sqrt((x^2)-3)?
0
reply
Rocious
Badges: 1
Rep:
?
#2
Report 9 years ago
#2
5x.sqrt(x^2 - 3) is a straightforward enough sub. you're prob ok there?

now for 2sqrt(x^2 - 3)

3cosh^2u - 3 = 3sinh^2u

and coshu differentiatess to sinhu so you can see what i'm getting at?
0
reply
01blowenm
Badges: 0
#3
Report Thread starter 9 years ago
#3
(Original post by Rocious)
5x.sqrt(x^2 - 3) is a straightforward enough sub. you're prob ok there?

now for 2sqrt(x^2 - 3)

3cosh^2u - 3 = 3sinh^2u

and coshu differentiatess to sinhu so you can see what i'm getting at?

cool, thank u. i wasnt expecting to use 2 diff methods.

could u also help with this one

(2x^2 + 1)sqrt(5-x)...
0
reply
Rocious
Badges: 1
Rep:
?
#4
Report 9 years ago
#4
i'd go parts with u = 2x^2 + 1 and dv = sqrt(5 - x) dx

2x^2 + 1 gets "simpler" when differentiated and sqrt(5 - x) doesn't really become harder to work with whether you differentiate or integrate.. it's still in the form of (ax + b)^n which is always nice. think with parts you just need to get a feel for it through doing it a lot.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • Cardiff Metropolitan University
    Undergraduate Open Day - Llandaff Campus Undergraduate
    Sat, 27 Apr '19
  • University of East Anglia
    Could you inspire the next generation? Find out more about becoming a Primary teacher with UEA… Postgraduate
    Sat, 27 Apr '19
  • Anglia Ruskin University
    Health, Education, Medicine and Social Care; Arts, Humanities and Social Sciences; Business and Law; Science and Engineering Undergraduate
    Sat, 27 Apr '19

Have you registered to vote?

Yes! (553)
37.82%
No - but I will (115)
7.87%
No - I don't want to (103)
7.05%
No - I can't vote (<18, not in UK, etc) (691)
47.26%

Watched Threads

View All
Latest
My Feed