5 marks, showing qn. Another question from GCE O Level Additional Mathematics (A-Math).
:)
Archives for October 2007
A-Math Integration of tan^2 x
Another question from O Level Additional Mathematics (A-Math).
lijun(: said...
i came across this qu that day, and i really want to clarify if the method i used is correct or not.int(tan^2x - x^3)
i changed it to int(sec^2x - 1 - x^3) instead, cos i don't think we can integrate tan.
is that feasible?
Absolutely. Since tan^2 x can't be integrated, you must think of alternative by making use of the relationship of tan^2 x + 1 = sec^2 x
A-Math P & C Clarification
Another question from O Level Additional Mathematics (A-Math).
lijun(: said...
hey. i just want to clarify something that i'm not very sure of.
is nCr x r! = nPr ??
By definition,
nCr = nPr/r!
Well, I never remember this 'rule'
For example, find the number of ways to form a 3 letter word from a,b,c,d,e
Student #1:
5C1*4C1*3C1
Student #2:
5P3
Both answers are correct though different approaches are taken, so no need to remember the 'rule'
:)