みなさんの使ってるシャーペン教えてください(愛用でおk)

MIN MID Kaweco KAWE CO GERMANY, SINCE 1883. orenz 3005 0.5 for 241

多様体の接空間に関する基底定理の証明です。g(q)=∫〜と定義した関数を微積分学の基本定理を用いながら変形してg(q)=g(0)+∑gᵢuⁱと導出するのですが、これがうまくいきません。 自分は、g(q)の式をまず両辺tで微分して、次に両辺uⁱで積分して、最後に両辺tで積分... Read More

12. Theorem.If{ = (x', , x") is a coordinate system in M at p, then its coordinate vectors d, lp, …… 0,l, forma basis for the tangent space T,(M); and D= E(x) 。 i=1 for all ve T(M). Proof. By the preceding remarks we can work solely on the coordinate neighborhood of G. Since u(c) = Othere is no loss of generality in assuming ど(p) = 0eR". Shrinking W if necessary gives E(W) = {qe R":|q| < } for some 8. Ifg is a smooth function on E(W) then for each 1 <isndefine og (tq) dt du g(9) = for all qe {(W). It follows using the fundamental theorem of calculus that g= g(0) + E&,u' on (W). Thus if fe &(M), setting g = f。' yields f= f(P) + Ex on U. Applying d/ax' gives f(p) = (f /0x)(P). Thus applying the tangent vector e to the formula gives (f) = 0+ E(x'(p) + E Ap)u(x) = E(Px). ず ax Since this holds for all f e &(M), the tangent vectors v and Z Ux') d,l, are equal. It remains to show that the coordinate vectors are linearly independent. But if ) a, o.l, = 0, then application to x' yields dxi 0=24 (P) = 2q d」= 4. In particular the (vector space) dimension of T,(M) is the same as the dimension of M.

多様体の接ベクトルに関する性質の証明なんですけど、(1)が分かりません。 素直に訳すと、(1)は「多様体上の滑らかな関数fとgが点pの座標近傍で同じなら、その接ベクトルv(f)とv(g)は同じになる」だと思うんですけど、証明でf(p)=0,g(p)=1と明らかに異なる値をと... Read More

11. Lemma. Let ve T,(M). (1) If f, ge F(M) are equal on a neighbor- hood of p, then Uf) = v(g). (2) If he F(M) is constant on a neighborhood of p, then u(h) 0. 三 Proof.(1) By linearity it suffices to show that if f = 0 on a neighbor- hood W of p, then u(f) = 0. Let g be a bump function at p with support in W; then fg = 0onall of M. But v(0)= u(0 + 0) = u(0) + u(0) implies v(0) = 0. Thus 0= (fg) = v(S)g(p) + f(p)v{g) = u(f), since f(p) (2) By(1) we can assume that h has constant value c on all of M. If 1 is the constant function of value 1, then 0 and g(p) 1. ニ (1) = (1.1) = (1)1 + lu(1) = 2v(1). Hence v(1) = 0, and v(h) = u(c· 1) = cu{1) = 0.

全体をアルファとしておいてから解いたのですがよくわかりません。 どなたかよろしくお願いします

sin Csince) fれた れ+んた) mo得数 nid

arcsin(since)=xが成り立つのは何故ですか？

おおまかな訳を教えてほしいです！！

For the first time ever, scientists have captured thought on video in real 員 t looks like a pink and purple grain of rice zipping around a large Dur- le 部 Really, that grain of rice is a thought moving around in the brain a zebrafish. Researchers at the National Institute ef 人Qene08 in Japan picked。 the brafish for this study because it has a see- -tbrough body By が the nes ofe zebrafish larvae, scientists can make certain parts of the fish glow ith Huofeseence. Since neurons in the brain use calcium to fire, the Saita- ia University researchers linked a protein to the fish's genes that glows the pf6Rence of calcium. When neurons fire in the fish's brain, the pro- in lights up,and we can seeit withthe helpofa 06808nt microscODe. je can make the invisible yastpeGDet most important,” said re- earcher Koichi Kawakami. ME 409 Ame tt Once yourve got a fish with a glowing brain, how do you know what it's inking about? Before recording the thought, the scientists fjgured out hich neurons in the fish's brain responded to movement. Then, they re- leased a paramecium, a tiny single-celled creature that the fsh love to eat- the paramecium moved, neurons in the fsh's brain Hit up in a pattern at matched the fish's motion. 5|So what does a fish think about? Thats easy 一 food! 9上 民【