CE MATHS [復制鏈接]

引用第14樓丹尼屎於2010-04-01 00:50發表的“”:
可以咁架咩? 我唔記得哂 [表情] [表情] [表情]

溫返下d定義就ok啦

引用第14樓丹尼屎於2010-04-01 00:50發表的“”:
可以咁架咩? 我唔記得哂 [表情] [表情] [表情]

10^y=x

100^(y/2) = x
100^y = x^2

引用第0樓朗仔於2010-03-31 21:44發表的“CE MATHS”:
let F( x ) be a polynomial. If F (x ) is disvisble by x-1 , WHich IS THE FACTOR OF F(2X+1) [表情]
A.X
B.X-3
C.2X-1
.......

you may consider another method
since
F (x ) is disvisble by x-1

so....we know
F(x)= (x-1)Q(x)

將2x+1代入去x

F(2x+1) = (2x+1-1)Q(2x+1)  
        =2x Q(2x+1)

obviously
x is the factor of F(2X+1)

引用第17樓反傳統於2010-04-01 01:24發表的“”:
you may consider another method
since
F (x ) is disvisble by x-1
.......

好勁

而家CE MATHS 咁深既..
我讀完AL都吾識TIM

sosad呢題琴晚先問完j3

差d唔識計....
a maths 個d數記得點計，但係maths d野唔係好記得

ax^2+2bx+c=0 has two equal real roots, which of the following is/ara true?

I. both roots are -b/a
II. a,b,c form a geometric progression
III. a,b,c form an arithmetic progresion


ans: I AND II

if a not equal to +-1, then 1+a^2+a^4+.....+ a^2n = ????

ans: 1-a^(2n+2) / 1-a^2

引用第19樓plmplm於2010-04-01 01:27發表的“”:
而家CE MATHS 咁深既..
我讀完AL都吾識TIM [表情]

我都唔記得晒

引用第22樓朗仔於2010-04-01 17:51發表的“”:
ax^2+2bx+c=0 has two real roots, which of the following is/ara true?
I. both roots are -b/a
II. a,b,c form a geometric progression
III. a,b,c form an arithmetic progresion
.......

你有冇打錯野?
好似有d矛盾

引用第23樓朗仔於2010-04-01 18:58發表的“”:
if a not equal to +-1, then 1+a^2+a^4+.....+ a^2n = ????
ans: 1-a^(2n+2) / 1-a^2

this is a GS
the first term = 1
common ratio = a^2
no. of terms = n+1

sum = [1-(common ratio)^no. of terms]/(1-common ratio)
= [1-a^2^n+1]/1-a^2
=(1-a^2n+2) / 1-a^2

引用第26樓rBB於2010-04-01 20:52發表的“”:
this is a GS
the first term = 1
common ratio = a^2
no. of terms = n+1
.......

no. of terms = n+1

咦,呢個點解既?

引用第27樓OldSosad於2010-04-01 20:54發表的“”:
no. of terms = n+1
咦,呢個點解既? [表情]

SUB number:
1+a^2+a^4+.....+ a^2n =

when n=1 : 1+a^2 ======>2 terms
when n=3 : 1+a^2+a^4+a^6 =======> 4 terms

引用第28樓rBB於2010-04-01 20:56發表的“”:
SUB number:
1+a^2+a^4+.....+ a^2n =
when n=1 : 1+a^2 ======>2 terms
.......

o thx