求下列函数在指定点的微分:
(1)y=x2+2x,x=0;
(2)y=exsinx,x=π/2.
(1)dy=d(x2+2x) =(2x+2xln2)dx, 所以当x=0时,有dy=ln2dx. (2)dy=d(exsinx) =exsinx(xsinx) =exsinx(sinx+xcosx)dx, 所以当x=π/2时,有dy=eπ/2dx .
求下列函数在指定点的微分:
(1)y=x2+2x,x=0;
(2)y=exsinx,x=π/2.
(1)dy=d(x2+2x) =(2x+2xln2)dx, 所以当x=0时,有dy=ln2dx. (2)dy=d(exsinx) =exsinx(xsinx) =exsinx(sinx+xcosx)dx, 所以当x=π/2时,有dy=eπ/2dx .