IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => GCE AS & A2 Level => Math => Topic started by: XFlufferzX on January 17, 2010, 11:02:30 am

Title: Integration help pleaseeee!!!!
Post by: XFlufferzX on January 17, 2010, 11:02:30 am

Da paper is attached
I stucked in question 3 b ii)

b ii)

= [ 2 ln 5 - 3 ln 3 + ln5] - [ 2n ln - 3l + ln3]

= " 3 ln 5 - 4 ln 3 " <---- I didnt know how to get this by subtracting [ 2 ln 5 - 3 ln 3 + ln5] from [ 2n ln - 3l + ln3]

can someone explain it fer meh!

thankss alot ;D

Title: Re: Integration help pleaseeee!!!!
Post by: astarmathsandphysics on January 17, 2010, 12:25:28 pm

[ 2 ln 5 - 3 ln 3 + ln5] - [ 2 ln1 - 3ln1 + ln3]
=[3ln5-3ln3]-[0-0+ln3] since ln1=0
=3ln5-3ln3-ln3=3ln5-4ln3=ln(5^3/3^4)=ln(125/81}

Title: Re: Integration help pleaseeee!!!!
Post by: XFlufferzX on January 17, 2010, 12:56:45 pm

Quote

[ 2 ln 5 - 3 ln 3 + ln5] - [ 2 ln1 - 3ln1 + ln3]
=[3ln5-3ln3]-[0-0+ln3] since ln1=0
=3ln5-3ln3-ln3=3ln5-4ln3=ln(5^3/3^4)=ln(125/81}

Thankss!!  :D