好悶 有無人問數

解釋下咩係injective surjective

injective: 唔會有y對應多個x

injective: f(x)=x
not injective: f(x)=x^2; (1=f(1)=f(-1))

surjective: 所有y都有其對應既x
surjective: f(x)=x
not surjective: f(x)=x^2; (f(x)=-1 -> error )

PS:以上例子都係講緊f:R->R

樓豬識m2既數?

識掛

皮膚+樣=身材

腳=？

J到出血-黑絲

如果n>1係整數，係咪會搵到正整數a,b,c令到4/n=1/a + 1/b +1/c?

好Q難 諗諗先

都係唔識
交比偉大既數學家們啦

留名

如果n>1係整數，係咪會搵到正整數a,b,c令到4/n=1/a + 1/b +1/c?

好Q難 諗諗先

都係唔識
交比偉大既數學家們啦

好似見過過post ,好似話有，但係個數值勁難計同勁撚大

如果n>1係整數，係咪會搵到正整數a,b,c令到4/n=1/a + 1/b +1/c?

好Q難 諗諗先

都係唔識
交比偉大既數學家們啦

好似見過過post ,好似話有，但係個數值勁難計同勁撚大

連登仔真係個個都IQ200

解釋下咩係injective surjective

injective: 如果y有對應既x, 則一定只對應唯一一個

injective: f(x)=x
not injective: f(x)=x^2; (1=f(1)=f(-1))

surjective: 所有y都有其對應既x
surjective: f(x)=x
not surjective: f(x)=x^2; (f(x)=-1 -> error )

PS:以上例子都係講緊f:R->R

無人問等我執一執先

成日唔識諗個triple integral coordinate angle range

成日唔識諗個triple integral coordinate angle range

見過兩種polar coordinate
我建議extend 2D果隻版本～
x-y plane theta照KEEP
再加個inclination angle phi由-90去到90度

好好記

突發！！
迷離哥哥ig已轉

新ig：dicky_gorgor
http://instagram.com/dicky_gorgor

dicdicboy
20 / PolyU / 23BRESS / Surveying

邊個黎
係咪上面果個理大SURVEY男神

突發！！
迷離哥哥ig已轉

新ig：dicky_gorgor
http://instagram.com/dicky_gorgor

dicdicboy
[i]20 / PolyU / 23BRESS / Surveying[i]

邊個黎
係咪上面果個理大SURVEY男神

[img]https://na.cx/i/xXvRj23.jpg[img]



唔識做

1
2;3
4;5;6
7;8;9;10

T(n)=n-th term of (1,3,6,10...)
a_n = 2^T(n)
b_1=2a_n = 2^(T(n)+1)
b_(n+1) = 2^T(n+1)

For n >1,
a_1=2^(T(n-1)+1)
a_1+a_2+...+a_n=GS sum=...
=(2^n-1)a_1
For n=1, this is also true.

b_1b_2...b_n
=2^[(T(n)+1)+(T(n)+2)+(T(n)+3)+...+(T(n)+(n+1))]
=2^[(n+1)T(n)+T(n+1)]
=...

咩係convolution

咩係convolution

2個signal 重疊出個新signal?

咩係convolution

Continuous analogue of discrete weighted sum

咩係convolution

我只能去WIKI COPY DEFN 比你

問我有咩睇法既話我都係半桶水，唔係好識
淨係學過做SIGNAL PROCESSING用

咩係convolution

我只能去WIKI COPY DEFN 比你

問我有咩睇法既話我都係半桶水，唔係好識
淨係學過做SIGNAL PROCESSING用

樓主都識Fourier transform line integral個堆，好想瘋狂問數

咩係convolution

我只能去WIKI COPY DEFN 比你

問我有咩睇法既話我都係半桶水，唔係好識
淨係學過做SIGNAL PROCESSING用

好想瘋狂問巴打數學

咩係convolution

我只能去WIKI COPY DEFN 比你

問我有咩睇法既話我都係半桶水，唔係好識
淨係學過做SIGNAL PROCESSING用

樓主都識Fourier transform line integral個堆，好想瘋狂問數

我覺得Theory緊要D
Fourier Transform你比張Table基本上人人識計（都入電腦嫁啦 ）
但佢可以SOLVE咩問題 原理係咩緊要D