forme algébrique i2=-1 zbarre=a-ib z*zbarre=a2+b2 z'/z=z'*zbarre/z*zbarre zbarre= conjugué de z ex: z=2+3i z'=-5+i 2z-3z'=(2*2+3i)-(-3-5+1)=19+3i z*z'=(2+3i)(-5+i)=-13-3i conjugué z+z'= conj -3+4i=-3-4i z/z'=2+3i/-5+i=-7-17i/26 forme trigo module z=r=sqrt(a2+b2) module z2=z*zbarre arg(z)=teta= cos(teta)=a/r sin(tet)=b/r z=rcos(teta)+isin(teta) cos sin 0 1 0 pi/6 sqrt(3)/2 1/2 pi/4 sqrt(2)/2 sqrt(2)/2 pi/3 1/2 sqrt(3)/2 pi/2 0 1 pi -1 0