Yahoo奇摩 網頁搜尋

Let S be open set in |R. For each x in S, there exists r(x... I(x)∪I(y) is contained in S and it contains I(x) and I(y). ...

旋轉一下，就可以證明出來了。 圖片參考：http://imgcld.yimg.com/8/n/AA00640066/o/101105130217513869707801.jpg

這是基本樣本空間的定義問題，5支鋼筆有2支好的，有3支是乾掉的。 Let G is a good pen found. D is a dry pen ...

grad f=(ycosxy,xcosxy), grad f(1,0)=(0,1) directional derivative of function f at the point(1,0) in the direction U=<3/5,-4/5> is the dot product of grad f(1,0) and U,that is,-4/5

...參考: Let U={(x,y)|0 < x^2+y^2}=R^2-(0,0). Let f(x,y)=(x^2-y^2, 2xy) for all (x,y) in U.We have det(Df(x,y))=|2x -2y||2y 2x|=4x^2+4y^2 >0for...

改為極坐標: x^2+y^2=4 , r=2 x^2+y^2=2x, r^2=2rcosθ, then r=2cosθ 如下圖紅色區域 圖片參考：http://imgcld.yimg.com/8/n/AD04686329/o/161006290550713872554260.jpg 原積分=∫[0~π/2]∫[2cosθ~2] √(4-r^2) * rdr dθ =∫[0~π/2] (-1/3)(4-r^2)^1.5 |[2cosθ~2] dθ = (8/3)∫[0~π/2] (sinθ)^3 dθ =(8/3)∫[0~π/2] [1-(cosθ)^2] sinθ dθ...

... by g^t . so for all a in G, a*(g^t)*a^-1 contains in T, let 's say eqaul to (g^t)^j. => a*(g^t)*a^-1=(g^t)^j every subgroup of T...

...cause its roots are irrational. Now, let g=x^2. Then f(g(x))=x^4+x^2+1=(x^2+1)^2-x^2...reducible over F. 2. I think that the "a" in the second line should be "r". In this...